Embed git in package

package.ps1 fetches PortableGit and embeds it in the package. This
eliminates all but one runtime dependency (MSVC++ Redistributable).

* Move Python into a new FOSS folder.

1 files changed, 0 insertions, 2647 deletions

diff --git a/Python/Dependencies/future-0.18.2/src/future/backports/urllib/request.py b/Python/Dependencies/future-0.18.2/src/future/backports/urllib/request.py
deleted file mode 100644
index baee540..0000000
--- a/Python/Dependencies/future-0.18.2/src/future/backports/urllib/request.py
+++ /dev/null
@@ -1,2647 +0,0 @@
-"""
-Ported using Python-Future from the Python 3.3 standard library.
-
-An extensible library for opening URLs using a variety of protocols
-
-The simplest way to use this module is to call the urlopen function,
-which accepts a string containing a URL or a Request object (described
-below).  It opens the URL and returns the results as file-like
-object; the returned object has some extra methods described below.
-
-The OpenerDirector manages a collection of Handler objects that do
-all the actual work.  Each Handler implements a particular protocol or
-option.  The OpenerDirector is a composite object that invokes the
-Handlers needed to open the requested URL.  For example, the
-HTTPHandler performs HTTP GET and POST requests and deals with
-non-error returns.  The HTTPRedirectHandler automatically deals with
-HTTP 301, 302, 303 and 307 redirect errors, and the HTTPDigestAuthHandler
-deals with digest authentication.
-
-urlopen(url, data=None) -- Basic usage is the same as original
-urllib.  pass the url and optionally data to post to an HTTP URL, and
-get a file-like object back.  One difference is that you can also pass
-a Request instance instead of URL.  Raises a URLError (subclass of
-IOError); for HTTP errors, raises an HTTPError, which can also be
-treated as a valid response.
-
-build_opener -- Function that creates a new OpenerDirector instance.
-Will install the default handlers.  Accepts one or more Handlers as
-arguments, either instances or Handler classes that it will
-instantiate.  If one of the argument is a subclass of the default
-handler, the argument will be installed instead of the default.
-
-install_opener -- Installs a new opener as the default opener.
-
-objects of interest:
-
-OpenerDirector -- Sets up the User Agent as the Python-urllib client and manages
-the Handler classes, while dealing with requests and responses.
-
-Request -- An object that encapsulates the state of a request.  The
-state can be as simple as the URL.  It can also include extra HTTP
-headers, e.g. a User-Agent.
-
-BaseHandler --
-
-internals:
-BaseHandler and parent
-_call_chain conventions
-
-Example usage:
-
-import urllib.request
-
-# set up authentication info
-authinfo = urllib.request.HTTPBasicAuthHandler()
-authinfo.add_password(realm='PDQ Application',
-                      uri='https://mahler:8092/site-updates.py',
-                      user='klem',
-                      passwd='geheim$parole')
-
-proxy_support = urllib.request.ProxyHandler({"http" : "http://ahad-haam:3128"})
-
-# build a new opener that adds authentication and caching FTP handlers
-opener = urllib.request.build_opener(proxy_support, authinfo,
-                                     urllib.request.CacheFTPHandler)
-
-# install it
-urllib.request.install_opener(opener)
-
-f = urllib.request.urlopen('http://www.python.org/')
-"""
-
-# XXX issues:
-# If an authentication error handler that tries to perform
-# authentication for some reason but fails, how should the error be
-# signalled?  The client needs to know the HTTP error code.  But if
-# the handler knows that the problem was, e.g., that it didn't know
-# that hash algo that requested in the challenge, it would be good to
-# pass that information along to the client, too.
-# ftp errors aren't handled cleanly
-# check digest against correct (i.e. non-apache) implementation
-
-# Possible extensions:
-# complex proxies  XXX not sure what exactly was meant by this
-# abstract factory for opener
-
-from __future__ import absolute_import, division, print_function, unicode_literals
-from future.builtins import bytes, dict, filter, input, int, map, open, str
-from future.utils import PY2, PY3, raise_with_traceback
-
-import base64
-import bisect
-import hashlib
-import array
-
-from future.backports import email
-from future.backports.http import client as http_client
-from .error import URLError, HTTPError, ContentTooShortError
-from .parse import (
-    urlparse, urlsplit, urljoin, unwrap, quote, unquote,
-    splittype, splithost, splitport, splituser, splitpasswd,
-    splitattr, splitquery, splitvalue, splittag, to_bytes, urlunparse)
-from .response import addinfourl, addclosehook
-
-import io
-import os
-import posixpath
-import re
-import socket
-import sys
-import time
-import tempfile
-import contextlib
-import warnings
-
-from future.utils import PY2
-
-if PY2:
-    from collections import Iterable
-else:
-    from collections.abc import Iterable
-
-# check for SSL
-try:
-    import ssl
-    # Not available in the SSL module in Py2:
-    from ssl import SSLContext
-except ImportError:
-    _have_ssl = False
-else:
-    _have_ssl = True
-
-__all__ = [
-    # Classes
-    'Request', 'OpenerDirector', 'BaseHandler', 'HTTPDefaultErrorHandler',
-    'HTTPRedirectHandler', 'HTTPCookieProcessor', 'ProxyHandler',
-    'HTTPPasswordMgr', 'HTTPPasswordMgrWithDefaultRealm',
-    'AbstractBasicAuthHandler', 'HTTPBasicAuthHandler', 'ProxyBasicAuthHandler',
-    'AbstractDigestAuthHandler', 'HTTPDigestAuthHandler', 'ProxyDigestAuthHandler',
-    'HTTPHandler', 'FileHandler', 'FTPHandler', 'CacheFTPHandler',
-    'UnknownHandler', 'HTTPErrorProcessor',
-    # Functions
-    'urlopen', 'install_opener', 'build_opener',
-    'pathname2url', 'url2pathname', 'getproxies',
-    # Legacy interface
-    'urlretrieve', 'urlcleanup', 'URLopener', 'FancyURLopener',
-]
-
-# used in User-Agent header sent
-__version__ = sys.version[:3]
-
-_opener = None
-def urlopen(url, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, **_3to2kwargs):
-    if 'cadefault' in _3to2kwargs: cadefault = _3to2kwargs['cadefault']; del _3to2kwargs['cadefault']
-    else: cadefault = False
-    if 'capath' in _3to2kwargs: capath = _3to2kwargs['capath']; del _3to2kwargs['capath']
-    else: capath = None
-    if 'cafile' in _3to2kwargs: cafile = _3to2kwargs['cafile']; del _3to2kwargs['cafile']
-    else: cafile = None
-    global _opener
-    if cafile or capath or cadefault:
-        if not _have_ssl:
-            raise ValueError('SSL support not available')
-        context = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
-        context.options |= ssl.OP_NO_SSLv2
-        context.verify_mode = ssl.CERT_REQUIRED
-        if cafile or capath:
-            context.load_verify_locations(cafile, capath)
-        else:
-            context.set_default_verify_paths()
-        https_handler = HTTPSHandler(context=context, check_hostname=True)
-        opener = build_opener(https_handler)
-    elif _opener is None:
-        _opener = opener = build_opener()
-    else:
-        opener = _opener
-    return opener.open(url, data, timeout)
-
-def install_opener(opener):
-    global _opener
-    _opener = opener
-
-_url_tempfiles = []
-def urlretrieve(url, filename=None, reporthook=None, data=None):
-    """
-    Retrieve a URL into a temporary location on disk.
-
-    Requires a URL argument. If a filename is passed, it is used as
-    the temporary file location. The reporthook argument should be
-    a callable that accepts a block number, a read size, and the
-    total file size of the URL target. The data argument should be
-    valid URL encoded data.
-
-    If a filename is passed and the URL points to a local resource,
-    the result is a copy from local file to new file.
-
-    Returns a tuple containing the path to the newly created
-    data file as well as the resulting HTTPMessage object.
-    """
-    url_type, path = splittype(url)
-
-    with contextlib.closing(urlopen(url, data)) as fp:
-        headers = fp.info()
-
-        # Just return the local path and the "headers" for file://
-        # URLs. No sense in performing a copy unless requested.
-        if url_type == "file" and not filename:
-            return os.path.normpath(path), headers
-
-        # Handle temporary file setup.
-        if filename:
-            tfp = open(filename, 'wb')
-        else:
-            tfp = tempfile.NamedTemporaryFile(delete=False)
-            filename = tfp.name
-            _url_tempfiles.append(filename)
-
-        with tfp:
-            result = filename, headers
-            bs = 1024*8
-            size = -1
-            read = 0
-            blocknum = 0
-            if "content-length" in headers:
-                size = int(headers["Content-Length"])
-
-            if reporthook:
-                reporthook(blocknum, bs, size)
-
-            while True:
-                block = fp.read(bs)
-                if not block:
-                    break
-                read += len(block)
-                tfp.write(block)
-                blocknum += 1
-                if reporthook:
-                    reporthook(blocknum, bs, size)
-
-    if size >= 0 and read < size:
-        raise ContentTooShortError(
-            "retrieval incomplete: got only %i out of %i bytes"
-            % (read, size), result)
-
-    return result
-
-def urlcleanup():
-    for temp_file in _url_tempfiles:
-        try:
-            os.unlink(temp_file)
-        except EnvironmentError:
-            pass
-
-    del _url_tempfiles[:]
-    global _opener
-    if _opener:
-        _opener = None
-
-if PY3:
-    _cut_port_re = re.compile(r":\d+$", re.ASCII)
-else:
-    _cut_port_re = re.compile(r":\d+$")
-
-def request_host(request):
-
-    """Return request-host, as defined by RFC 2965.
-
-    Variation from RFC: returned value is lowercased, for convenient
-    comparison.
-
-    """
-    url = request.full_url
-    host = urlparse(url)[1]
-    if host == "":
-        host = request.get_header("Host", "")
-
-    # remove port, if present
-    host = _cut_port_re.sub("", host, 1)
-    return host.lower()
-
-class Request(object):
-
-    def __init__(self, url, data=None, headers={},
-                 origin_req_host=None, unverifiable=False,
-                 method=None):
-        # unwrap('<URL:type://host/path>') --> 'type://host/path'
-        self.full_url = unwrap(url)
-        self.full_url, self.fragment = splittag(self.full_url)
-        self.data = data
-        self.headers = {}
-        self._tunnel_host = None
-        for key, value in headers.items():
-            self.add_header(key, value)
-        self.unredirected_hdrs = {}
-        if origin_req_host is None:
-            origin_req_host = request_host(self)
-        self.origin_req_host = origin_req_host
-        self.unverifiable = unverifiable
-        self.method = method
-        self._parse()
-
-    def _parse(self):
-        self.type, rest = splittype(self.full_url)
-        if self.type is None:
-            raise ValueError("unknown url type: %r" % self.full_url)
-        self.host, self.selector = splithost(rest)
-        if self.host:
-            self.host = unquote(self.host)
-
-    def get_method(self):
-        """Return a string indicating the HTTP request method."""
-        if self.method is not None:
-            return self.method
-        elif self.data is not None:
-            return "POST"
-        else:
-            return "GET"
-
-    def get_full_url(self):
-        if self.fragment:
-            return '%s#%s' % (self.full_url, self.fragment)
-        else:
-            return self.full_url
-
-    # Begin deprecated methods
-
-    def add_data(self, data):
-        msg = "Request.add_data method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        self.data = data
-
-    def has_data(self):
-        msg = "Request.has_data method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.data is not None
-
-    def get_data(self):
-        msg = "Request.get_data method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.data
-
-    def get_type(self):
-        msg = "Request.get_type method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.type
-
-    def get_host(self):
-        msg = "Request.get_host method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.host
-
-    def get_selector(self):
-        msg = "Request.get_selector method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.selector
-
-    def is_unverifiable(self):
-        msg = "Request.is_unverifiable method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.unverifiable
-
-    def get_origin_req_host(self):
-        msg = "Request.get_origin_req_host method is deprecated."
-        warnings.warn(msg, DeprecationWarning, stacklevel=1)
-        return self.origin_req_host
-
-    # End deprecated methods
-
-    def set_proxy(self, host, type):
-        if self.type == 'https' and not self._tunnel_host:
-            self._tunnel_host = self.host
-        else:
-            self.type= type
-            self.selector = self.full_url
-        self.host = host
-
-    def has_proxy(self):
-        return self.selector == self.full_url
-
-    def add_header(self, key, val):
-        # useful for something like authentication
-        self.headers[key.capitalize()] = val
-
-    def add_unredirected_header(self, key, val):
-        # will not be added to a redirected request
-        self.unredirected_hdrs[key.capitalize()] = val
-
-    def has_header(self, header_name):
-        return (header_name in self.headers or
-                header_name in self.unredirected_hdrs)
-
-    def get_header(self, header_name, default=None):
-        return self.headers.get(
-            header_name,
-            self.unredirected_hdrs.get(header_name, default))
-
-    def header_items(self):
-        hdrs = self.unredirected_hdrs.copy()
-        hdrs.update(self.headers)
-        return list(hdrs.items())
-
-class OpenerDirector(object):
-    def __init__(self):
-        client_version = "Python-urllib/%s" % __version__
-        self.addheaders = [('User-agent', client_version)]
-        # self.handlers is retained only for backward compatibility
-        self.handlers = []
-        # manage the individual handlers
-        self.handle_open = {}
-        self.handle_error = {}
-        self.process_response = {}
-        self.process_request = {}
-
-    def add_handler(self, handler):
-        if not hasattr(handler, "add_parent"):
-            raise TypeError("expected BaseHandler instance, got %r" %
-                            type(handler))
-
-        added = False
-        for meth in dir(handler):
-            if meth in ["redirect_request", "do_open", "proxy_open"]:
-                # oops, coincidental match
-                continue
-
-            i = meth.find("_")
-            protocol = meth[:i]
-            condition = meth[i+1:]
-
-            if condition.startswith("error"):
-                j = condition.find("_") + i + 1
-                kind = meth[j+1:]
-                try:
-                    kind = int(kind)
-                except ValueError:
-                    pass
-                lookup = self.handle_error.get(protocol, {})
-                self.handle_error[protocol] = lookup
-            elif condition == "open":
-                kind = protocol
-                lookup = self.handle_open
-            elif condition == "response":
-                kind = protocol
-                lookup = self.process_response
-            elif condition == "request":
-                kind = protocol
-                lookup = self.process_request
-            else:
-                continue
-
-            handlers = lookup.setdefault(kind, [])
-            if handlers:
-                bisect.insort(handlers, handler)
-            else:
-                handlers.append(handler)
-            added = True
-
-        if added:
-            bisect.insort(self.handlers, handler)
-            handler.add_parent(self)
-
-    def close(self):
-        # Only exists for backwards compatibility.
-        pass
-
-    def _call_chain(self, chain, kind, meth_name, *args):
-        # Handlers raise an exception if no one else should try to handle
-        # the request, or return None if they can't but another handler
-        # could.  Otherwise, they return the response.
-        handlers = chain.get(kind, ())
-        for handler in handlers:
-            func = getattr(handler, meth_name)
-            result = func(*args)
-            if result is not None:
-                return result
-
-    def open(self, fullurl, data=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
-        """
-        Accept a URL or a Request object
-
-        Python-Future: if the URL is passed as a byte-string, decode it first.
-        """
-        if isinstance(fullurl, bytes):
-            fullurl = fullurl.decode()
-        if isinstance(fullurl, str):
-            req = Request(fullurl, data)
-        else:
-            req = fullurl
-            if data is not None:
-                req.data = data
-
-        req.timeout = timeout
-        protocol = req.type
-
-        # pre-process request
-        meth_name = protocol+"_request"
-        for processor in self.process_request.get(protocol, []):
-            meth = getattr(processor, meth_name)
-            req = meth(req)
-
-        response = self._open(req, data)
-
-        # post-process response
-        meth_name = protocol+"_response"
-        for processor in self.process_response.get(protocol, []):
-            meth = getattr(processor, meth_name)
-            response = meth(req, response)
-
-        return response
-
-    def _open(self, req, data=None):
-        result = self._call_chain(self.handle_open, 'default',
-                                  'default_open', req)
-        if result:
-            return result
-
-        protocol = req.type
-        result = self._call_chain(self.handle_open, protocol, protocol +
-                                  '_open', req)
-        if result:
-            return result
-
-        return self._call_chain(self.handle_open, 'unknown',
-                                'unknown_open', req)
-
-    def error(self, proto, *args):
-        if proto in ('http', 'https'):
-            # XXX http[s] protocols are special-cased
-            dict = self.handle_error['http'] # https is not different than http
-            proto = args[2]  # YUCK!
-            meth_name = 'http_error_%s' % proto
-            http_err = 1
-            orig_args = args
-        else:
-            dict = self.handle_error
-            meth_name = proto + '_error'
-            http_err = 0
-        args = (dict, proto, meth_name) + args
-        result = self._call_chain(*args)
-        if result:
-            return result
-
-        if http_err:
-            args = (dict, 'default', 'http_error_default') + orig_args
-            return self._call_chain(*args)
-
-# XXX probably also want an abstract factory that knows when it makes
-# sense to skip a superclass in favor of a subclass and when it might
-# make sense to include both
-
-def build_opener(*handlers):
-    """Create an opener object from a list of handlers.
-
-    The opener will use several default handlers, including support
-    for HTTP, FTP and when applicable HTTPS.
-
-    If any of the handlers passed as arguments are subclasses of the
-    default handlers, the default handlers will not be used.
-    """
-    def isclass(obj):
-        return isinstance(obj, type) or hasattr(obj, "__bases__")
-
-    opener = OpenerDirector()
-    default_classes = [ProxyHandler, UnknownHandler, HTTPHandler,
-                       HTTPDefaultErrorHandler, HTTPRedirectHandler,
-                       FTPHandler, FileHandler, HTTPErrorProcessor]
-    if hasattr(http_client, "HTTPSConnection"):
-        default_classes.append(HTTPSHandler)
-    skip = set()
-    for klass in default_classes:
-        for check in handlers:
-            if isclass(check):
-                if issubclass(check, klass):
-                    skip.add(klass)
-            elif isinstance(check, klass):
-                skip.add(klass)
-    for klass in skip:
-        default_classes.remove(klass)
-
-    for klass in default_classes:
-        opener.add_handler(klass())
-
-    for h in handlers:
-        if isclass(h):
-            h = h()
-        opener.add_handler(h)
-    return opener
-
-class BaseHandler(object):
-    handler_order = 500
-
-    def add_parent(self, parent):
-        self.parent = parent
-
-    def close(self):
-        # Only exists for backwards compatibility
-        pass
-
-    def __lt__(self, other):
-        if not hasattr(other, "handler_order"):
-            # Try to preserve the old behavior of having custom classes
-            # inserted after default ones (works only for custom user
-            # classes which are not aware of handler_order).
-            return True
-        return self.handler_order < other.handler_order
-
-
-class HTTPErrorProcessor(BaseHandler):
-    """Process HTTP error responses."""
-    handler_order = 1000  # after all other processing
-
-    def http_response(self, request, response):
-        code, msg, hdrs = response.code, response.msg, response.info()
-
-        # According to RFC 2616, "2xx" code indicates that the client's
-        # request was successfully received, understood, and accepted.
-        if not (200 <= code < 300):
-            response = self.parent.error(
-                'http', request, response, code, msg, hdrs)
-
-        return response
-
-    https_response = http_response
-
-class HTTPDefaultErrorHandler(BaseHandler):
-    def http_error_default(self, req, fp, code, msg, hdrs):
-        raise HTTPError(req.full_url, code, msg, hdrs, fp)
-
-class HTTPRedirectHandler(BaseHandler):
-    # maximum number of redirections to any single URL
-    # this is needed because of the state that cookies introduce
-    max_repeats = 4
-    # maximum total number of redirections (regardless of URL) before
-    # assuming we're in a loop
-    max_redirections = 10
-
-    def redirect_request(self, req, fp, code, msg, headers, newurl):
-        """Return a Request or None in response to a redirect.
-
-        This is called by the http_error_30x methods when a
-        redirection response is received.  If a redirection should
-        take place, return a new Request to allow http_error_30x to
-        perform the redirect.  Otherwise, raise HTTPError if no-one
-        else should try to handle this url.  Return None if you can't
-        but another Handler might.
-        """
-        m = req.get_method()
-        if (not (code in (301, 302, 303, 307) and m in ("GET", "HEAD")
-            or code in (301, 302, 303) and m == "POST")):
-            raise HTTPError(req.full_url, code, msg, headers, fp)
-
-        # Strictly (according to RFC 2616), 301 or 302 in response to
-        # a POST MUST NOT cause a redirection without confirmation
-        # from the user (of urllib.request, in this case).  In practice,
-        # essentially all clients do redirect in this case, so we do
-        # the same.
-        # be conciliant with URIs containing a space
-        newurl = newurl.replace(' ', '%20')
-        CONTENT_HEADERS = ("content-length", "content-type")
-        newheaders = dict((k, v) for k, v in req.headers.items()
-                          if k.lower() not in CONTENT_HEADERS)
-        return Request(newurl,
-                       headers=newheaders,
-                       origin_req_host=req.origin_req_host,
-                       unverifiable=True)
-
-    # Implementation note: To avoid the server sending us into an
-    # infinite loop, the request object needs to track what URLs we
-    # have already seen.  Do this by adding a handler-specific
-    # attribute to the Request object.
-    def http_error_302(self, req, fp, code, msg, headers):
-        # Some servers (incorrectly) return multiple Location headers
-        # (so probably same goes for URI).  Use first header.
-        if "location" in headers:
-            newurl = headers["location"]
-        elif "uri" in headers:
-            newurl = headers["uri"]
-        else:
-            return
-
-        # fix a possible malformed URL
-        urlparts = urlparse(newurl)
-
-        # For security reasons we don't allow redirection to anything other
-        # than http, https or ftp.
-
-        if urlparts.scheme not in ('http', 'https', 'ftp', ''):
-            raise HTTPError(
-                newurl, code,
-                "%s - Redirection to url '%s' is not allowed" % (msg, newurl),
-                headers, fp)
-
-        if not urlparts.path:
-            urlparts = list(urlparts)
-            urlparts[2] = "/"
-        newurl = urlunparse(urlparts)
-
-        newurl = urljoin(req.full_url, newurl)
-
-        # XXX Probably want to forget about the state of the current
-        # request, although that might interact poorly with other
-        # handlers that also use handler-specific request attributes
-        new = self.redirect_request(req, fp, code, msg, headers, newurl)
-        if new is None:
-            return
-
-        # loop detection
-        # .redirect_dict has a key url if url was previously visited.
-        if hasattr(req, 'redirect_dict'):
-            visited = new.redirect_dict = req.redirect_dict
-            if (visited.get(newurl, 0) >= self.max_repeats or
-                len(visited) >= self.max_redirections):
-                raise HTTPError(req.full_url, code,
-                                self.inf_msg + msg, headers, fp)
-        else:
-            visited = new.redirect_dict = req.redirect_dict = {}
-        visited[newurl] = visited.get(newurl, 0) + 1
-
-        # Don't close the fp until we are sure that we won't use it
-        # with HTTPError.
-        fp.read()
-        fp.close()
-
-        return self.parent.open(new, timeout=req.timeout)
-
-    http_error_301 = http_error_303 = http_error_307 = http_error_302
-
-    inf_msg = "The HTTP server returned a redirect error that would " \
-              "lead to an infinite loop.\n" \
-              "The last 30x error message was:\n"
-
-
-def _parse_proxy(proxy):
-    """Return (scheme, user, password, host/port) given a URL or an authority.
-
-    If a URL is supplied, it must have an authority (host:port) component.
-    According to RFC 3986, having an authority component means the URL must
-    have two slashes after the scheme:
-
-    >>> _parse_proxy('file:/ftp.example.com/')
-    Traceback (most recent call last):
-    ValueError: proxy URL with no authority: 'file:/ftp.example.com/'
-
-    The first three items of the returned tuple may be None.
-
-    Examples of authority parsing:
-
-    >>> _parse_proxy('proxy.example.com')
-    (None, None, None, 'proxy.example.com')
-    >>> _parse_proxy('proxy.example.com:3128')
-    (None, None, None, 'proxy.example.com:3128')
-
-    The authority component may optionally include userinfo (assumed to be
-    username:password):
-
-    >>> _parse_proxy('joe:password@proxy.example.com')
-    (None, 'joe', 'password', 'proxy.example.com')
-    >>> _parse_proxy('joe:password@proxy.example.com:3128')
-    (None, 'joe', 'password', 'proxy.example.com:3128')
-
-    Same examples, but with URLs instead:
-
-    >>> _parse_proxy('http://proxy.example.com/')
-    ('http', None, None, 'proxy.example.com')
-    >>> _parse_proxy('http://proxy.example.com:3128/')
-    ('http', None, None, 'proxy.example.com:3128')
-    >>> _parse_proxy('http://joe:password@proxy.example.com/')
-    ('http', 'joe', 'password', 'proxy.example.com')
-    >>> _parse_proxy('http://joe:password@proxy.example.com:3128')
-    ('http', 'joe', 'password', 'proxy.example.com:3128')
-
-    Everything after the authority is ignored:
-
-    >>> _parse_proxy('ftp://joe:password@proxy.example.com/rubbish:3128')
-    ('ftp', 'joe', 'password', 'proxy.example.com')
-
-    Test for no trailing '/' case:
-
-    >>> _parse_proxy('http://joe:password@proxy.example.com')
-    ('http', 'joe', 'password', 'proxy.example.com')
-
-    """
-    scheme, r_scheme = splittype(proxy)
-    if not r_scheme.startswith("/"):
-        # authority
-        scheme = None
-        authority = proxy
-    else:
-        # URL
-        if not r_scheme.startswith("//"):
-            raise ValueError("proxy URL with no authority: %r" % proxy)
-        # We have an authority, so for RFC 3986-compliant URLs (by ss 3.
-        # and 3.3.), path is empty or starts with '/'
-        end = r_scheme.find("/", 2)
-        if end == -1:
-            end = None
-        authority = r_scheme[2:end]
-    userinfo, hostport = splituser(authority)
-    if userinfo is not None:
-        user, password = splitpasswd(userinfo)
-    else:
-        user = password = None
-    return scheme, user, password, hostport
-
-class ProxyHandler(BaseHandler):
-    # Proxies must be in front
-    handler_order = 100
-
-    def __init__(self, proxies=None):
-        if proxies is None:
-            proxies = getproxies()
-        assert hasattr(proxies, 'keys'), "proxies must be a mapping"
-        self.proxies = proxies
-        for type, url in proxies.items():
-            setattr(self, '%s_open' % type,
-                    lambda r, proxy=url, type=type, meth=self.proxy_open:
-                        meth(r, proxy, type))
-
-    def proxy_open(self, req, proxy, type):
-        orig_type = req.type
-        proxy_type, user, password, hostport = _parse_proxy(proxy)
-        if proxy_type is None:
-            proxy_type = orig_type
-
-        if req.host and proxy_bypass(req.host):
-            return None
-
-        if user and password:
-            user_pass = '%s:%s' % (unquote(user),
-                                   unquote(password))
-            creds = base64.b64encode(user_pass.encode()).decode("ascii")
-            req.add_header('Proxy-authorization', 'Basic ' + creds)
-        hostport = unquote(hostport)
-        req.set_proxy(hostport, proxy_type)
-        if orig_type == proxy_type or orig_type == 'https':
-            # let other handlers take care of it
-            return None
-        else:
-            # need to start over, because the other handlers don't
-            # grok the proxy's URL type
-            # e.g. if we have a constructor arg proxies like so:
-            # {'http': 'ftp://proxy.example.com'}, we may end up turning
-            # a request for http://acme.example.com/a into one for
-            # ftp://proxy.example.com/a
-            return self.parent.open(req, timeout=req.timeout)
-
-class HTTPPasswordMgr(object):
-
-    def __init__(self):
-        self.passwd = {}
-
-    def add_password(self, realm, uri, user, passwd):
-        # uri could be a single URI or a sequence
-        if isinstance(uri, str):
-            uri = [uri]
-        if realm not in self.passwd:
-            self.passwd[realm] = {}
-        for default_port in True, False:
-            reduced_uri = tuple(
-                [self.reduce_uri(u, default_port) for u in uri])
-            self.passwd[realm][reduced_uri] = (user, passwd)
-
-    def find_user_password(self, realm, authuri):
-        domains = self.passwd.get(realm, {})
-        for default_port in True, False:
-            reduced_authuri = self.reduce_uri(authuri, default_port)
-            for uris, authinfo in domains.items():
-                for uri in uris:
-                    if self.is_suburi(uri, reduced_authuri):
-                        return authinfo
-        return None, None
-
-    def reduce_uri(self, uri, default_port=True):
-        """Accept authority or URI and extract only the authority and path."""
-        # note HTTP URLs do not have a userinfo component
-        parts = urlsplit(uri)
-        if parts[1]:
-            # URI
-            scheme = parts[0]
-            authority = parts[1]
-            path = parts[2] or '/'
-        else:
-            # host or host:port
-            scheme = None
-            authority = uri
-            path = '/'
-        host, port = splitport(authority)
-        if default_port and port is None and scheme is not None:
-            dport = {"http": 80,
-                     "https": 443,
-                     }.get(scheme)
-            if dport is not None:
-                authority = "%s:%d" % (host, dport)
-        return authority, path
-
-    def is_suburi(self, base, test):
-        """Check if test is below base in a URI tree
-
-        Both args must be URIs in reduced form.
-        """
-        if base == test:
-            return True
-        if base[0] != test[0]:
-            return False
-        common = posixpath.commonprefix((base[1], test[1]))
-        if len(common) == len(base[1]):
-            return True
-        return False
-
-
-class HTTPPasswordMgrWithDefaultRealm(HTTPPasswordMgr):
-
-    def find_user_password(self, realm, authuri):
-        user, password = HTTPPasswordMgr.find_user_password(self, realm,
-                                                            authuri)
-        if user is not None:
-            return user, password
-        return HTTPPasswordMgr.find_user_password(self, None, authuri)
-
-
-class AbstractBasicAuthHandler(object):
-
-    # XXX this allows for multiple auth-schemes, but will stupidly pick
-    # the last one with a realm specified.
-
-    # allow for double- and single-quoted realm values
-    # (single quotes are a violation of the RFC, but appear in the wild)
-    rx = re.compile('(?:.*,)*[ \t]*([^ \t]+)[ \t]+'
-                    'realm=(["\']?)([^"\']*)\\2', re.I)
-
-    # XXX could pre-emptively send auth info already accepted (RFC 2617,
-    # end of section 2, and section 1.2 immediately after "credentials"
-    # production).
-
-    def __init__(self, password_mgr=None):
-        if password_mgr is None:
-            password_mgr = HTTPPasswordMgr()
-        self.passwd = password_mgr
-        self.add_password = self.passwd.add_password
-        self.retried = 0
-
-    def reset_retry_count(self):
-        self.retried = 0
-
-    def http_error_auth_reqed(self, authreq, host, req, headers):
-        # host may be an authority (without userinfo) or a URL with an
-        # authority
-        # XXX could be multiple headers
-        authreq = headers.get(authreq, None)
-
-        if self.retried > 5:
-            # retry sending the username:password 5 times before failing.
-            raise HTTPError(req.get_full_url(), 401, "basic auth failed",
-                    headers, None)
-        else:
-            self.retried += 1
-
-        if authreq:
-            scheme = authreq.split()[0]
-            if scheme.lower() != 'basic':
-                raise ValueError("AbstractBasicAuthHandler does not"
-                                 " support the following scheme: '%s'" %
-                                 scheme)
-            else:
-                mo = AbstractBasicAuthHandler.rx.search(authreq)
-                if mo:
-                    scheme, quote, realm = mo.groups()
-                    if quote not in ['"',"'"]:
-                        warnings.warn("Basic Auth Realm was unquoted",
-                                      UserWarning, 2)
-                    if scheme.lower() == 'basic':
-                        response = self.retry_http_basic_auth(host, req, realm)
-                        if response and response.code != 401:
-                            self.retried = 0
-                        return response
-
-    def retry_http_basic_auth(self, host, req, realm):
-        user, pw = self.passwd.find_user_password(realm, host)
-        if pw is not None:
-            raw = "%s:%s" % (user, pw)
-            auth = "Basic " + base64.b64encode(raw.encode()).decode("ascii")
-            if req.headers.get(self.auth_header, None) == auth:
-                return None
-            req.add_unredirected_header(self.auth_header, auth)
-            return self.parent.open(req, timeout=req.timeout)
-        else:
-            return None
-
-
-class HTTPBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
-
-    auth_header = 'Authorization'
-
-    def http_error_401(self, req, fp, code, msg, headers):
-        url = req.full_url
-        response = self.http_error_auth_reqed('www-authenticate',
-                                          url, req, headers)
-        self.reset_retry_count()
-        return response
-
-
-class ProxyBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler):
-
-    auth_header = 'Proxy-authorization'
-
-    def http_error_407(self, req, fp, code, msg, headers):
-        # http_error_auth_reqed requires that there is no userinfo component in
-        # authority.  Assume there isn't one, since urllib.request does not (and
-        # should not, RFC 3986 s. 3.2.1) support requests for URLs containing
-        # userinfo.
-        authority = req.host
-        response = self.http_error_auth_reqed('proxy-authenticate',
-                                          authority, req, headers)
-        self.reset_retry_count()
-        return response
-
-
-# Return n random bytes.
-_randombytes = os.urandom
-
-
-class AbstractDigestAuthHandler(object):
-    # Digest authentication is specified in RFC 2617.
-
-    # XXX The client does not inspect the Authentication-Info header
-    # in a successful response.
-
-    # XXX It should be possible to test this implementation against
-    # a mock server that just generates a static set of challenges.
-
-    # XXX qop="auth-int" supports is shaky
-
-    def __init__(self, passwd=None):
-        if passwd is None:
-            passwd = HTTPPasswordMgr()
-        self.passwd = passwd
-        self.add_password = self.passwd.add_password
-        self.retried = 0
-        self.nonce_count = 0
-        self.last_nonce = None
-
-    def reset_retry_count(self):
-        self.retried = 0
-
-    def http_error_auth_reqed(self, auth_header, host, req, headers):
-        authreq = headers.get(auth_header, None)
-        if self.retried > 5:
-            # Don't fail endlessly - if we failed once, we'll probably
-            # fail a second time. Hm. Unless the Password Manager is
-            # prompting for the information. Crap. This isn't great
-            # but it's better than the current 'repeat until recursion
-            # depth exceeded' approach <wink>
-            raise HTTPError(req.full_url, 401, "digest auth failed",
-                            headers, None)
-        else:
-            self.retried += 1
-        if authreq:
-            scheme = authreq.split()[0]
-            if scheme.lower() == 'digest':
-                return self.retry_http_digest_auth(req, authreq)
-            elif scheme.lower() != 'basic':
-                raise ValueError("AbstractDigestAuthHandler does not support"
-                                 " the following scheme: '%s'" % scheme)
-
-    def retry_http_digest_auth(self, req, auth):
-        token, challenge = auth.split(' ', 1)
-        chal = parse_keqv_list(filter(None, parse_http_list(challenge)))
-        auth = self.get_authorization(req, chal)
-        if auth:
-            auth_val = 'Digest %s' % auth
-            if req.headers.get(self.auth_header, None) == auth_val:
-                return None
-            req.add_unredirected_header(self.auth_header, auth_val)
-            resp = self.parent.open(req, timeout=req.timeout)
-            return resp
-
-    def get_cnonce(self, nonce):
-        # The cnonce-value is an opaque
-        # quoted string value provided by the client and used by both client
-        # and server to avoid chosen plaintext attacks, to provide mutual
-        # authentication, and to provide some message integrity protection.
-        # This isn't a fabulous effort, but it's probably Good Enough.
-        s = "%s:%s:%s:" % (self.nonce_count, nonce, time.ctime())
-        b = s.encode("ascii") + _randombytes(8)
-        dig = hashlib.sha1(b).hexdigest()
-        return dig[:16]
-
-    def get_authorization(self, req, chal):
-        try:
-            realm = chal['realm']
-            nonce = chal['nonce']
-            qop = chal.get('qop')
-            algorithm = chal.get('algorithm', 'MD5')
-            # mod_digest doesn't send an opaque, even though it isn't
-            # supposed to be optional
-            opaque = chal.get('opaque', None)
-        except KeyError:
-            return None
-
-        H, KD = self.get_algorithm_impls(algorithm)
-        if H is None:
-            return None
-
-        user, pw = self.passwd.find_user_password(realm, req.full_url)
-        if user is None:
-            return None
-
-        # XXX not implemented yet
-        if req.data is not None:
-            entdig = self.get_entity_digest(req.data, chal)
-        else:
-            entdig = None
-
-        A1 = "%s:%s:%s" % (user, realm, pw)
-        A2 = "%s:%s" % (req.get_method(),
-                        # XXX selector: what about proxies and full urls
-                        req.selector)
-        if qop == 'auth':
-            if nonce == self.last_nonce:
-                self.nonce_count += 1
-            else:
-                self.nonce_count = 1
-                self.last_nonce = nonce
-            ncvalue = '%08x' % self.nonce_count
-            cnonce = self.get_cnonce(nonce)
-            noncebit = "%s:%s:%s:%s:%s" % (nonce, ncvalue, cnonce, qop, H(A2))
-            respdig = KD(H(A1), noncebit)
-        elif qop is None:
-            respdig = KD(H(A1), "%s:%s" % (nonce, H(A2)))
-        else:
-            # XXX handle auth-int.
-            raise URLError("qop '%s' is not supported." % qop)
-
-        # XXX should the partial digests be encoded too?
-
-        base = 'username="%s", realm="%s", nonce="%s", uri="%s", ' \
-               'response="%s"' % (user, realm, nonce, req.selector,
-                                  respdig)
-        if opaque:
-            base += ', opaque="%s"' % opaque
-        if entdig:
-            base += ', digest="%s"' % entdig
-        base += ', algorithm="%s"' % algorithm
-        if qop:
-            base += ', qop=auth, nc=%s, cnonce="%s"' % (ncvalue, cnonce)
-        return base
-
-    def get_algorithm_impls(self, algorithm):
-        # lambdas assume digest modules are imported at the top level
-        if algorithm == 'MD5':
-            H = lambda x: hashlib.md5(x.encode("ascii")).hexdigest()
-        elif algorithm == 'SHA':
-            H = lambda x: hashlib.sha1(x.encode("ascii")).hexdigest()
-        # XXX MD5-sess
-        KD = lambda s, d: H("%s:%s" % (s, d))
-        return H, KD
-
-    def get_entity_digest(self, data, chal):
-        # XXX not implemented yet
-        return None
-
-
-class HTTPDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
-    """An authentication protocol defined by RFC 2069
-
-    Digest authentication improves on basic authentication because it
-    does not transmit passwords in the clear.
-    """
-
-    auth_header = 'Authorization'
-    handler_order = 490  # before Basic auth
-
-    def http_error_401(self, req, fp, code, msg, headers):
-        host = urlparse(req.full_url)[1]
-        retry = self.http_error_auth_reqed('www-authenticate',
-                                           host, req, headers)
-        self.reset_retry_count()
-        return retry
-
-
-class ProxyDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
-
-    auth_header = 'Proxy-Authorization'
-    handler_order = 490  # before Basic auth
-
-    def http_error_407(self, req, fp, code, msg, headers):
-        host = req.host
-        retry = self.http_error_auth_reqed('proxy-authenticate',
-                                           host, req, headers)
-        self.reset_retry_count()
-        return retry
-
-class AbstractHTTPHandler(BaseHandler):
-
-    def __init__(self, debuglevel=0):
-        self._debuglevel = debuglevel
-
-    def set_http_debuglevel(self, level):
-        self._debuglevel = level
-
-    def do_request_(self, request):
-        host = request.host
-        if not host:
-            raise URLError('no host given')
-
-        if request.data is not None:  # POST
-            data = request.data
-            if isinstance(data, str):
-                msg = "POST data should be bytes or an iterable of bytes. " \
-                      "It cannot be of type str."
-                raise TypeError(msg)
-            if not request.has_header('Content-type'):
-                request.add_unredirected_header(
-                    'Content-type',
-                    'application/x-www-form-urlencoded')
-            if not request.has_header('Content-length'):
-                size = None
-                try:
-                    ### For Python-Future:
-                    if PY2 and isinstance(data, array.array):
-                        # memoryviews of arrays aren't supported
-                        # in Py2.7. (e.g. memoryview(array.array('I',
-                        # [1, 2, 3, 4])) raises a TypeError.)
-                        # So we calculate the size manually instead:
-                        size = len(data) * data.itemsize
-                    ###
-                    else:
-                        mv = memoryview(data)
-                        size = len(mv) * mv.itemsize
-                except TypeError:
-                    if isinstance(data, Iterable):
-                        raise ValueError("Content-Length should be specified "
-                                "for iterable data of type %r %r" % (type(data),
-                                data))
-                else:
-                    request.add_unredirected_header(
-                            'Content-length', '%d' % size)
-
-        sel_host = host
-        if request.has_proxy():
-            scheme, sel = splittype(request.selector)
-            sel_host, sel_path = splithost(sel)
-        if not request.has_header('Host'):
-            request.add_unredirected_header('Host', sel_host)
-        for name, value in self.parent.addheaders:
-            name = name.capitalize()
-            if not request.has_header(name):
-                request.add_unredirected_header(name, value)
-
-        return request
-
-    def do_open(self, http_class, req, **http_conn_args):
-        """Return an HTTPResponse object for the request, using http_class.
-
-        http_class must implement the HTTPConnection API from http.client.
-        """
-        host = req.host
-        if not host:
-            raise URLError('no host given')
-
-        # will parse host:port
-        h = http_class(host, timeout=req.timeout, **http_conn_args)
-
-        headers = dict(req.unredirected_hdrs)
-        headers.update(dict((k, v) for k, v in req.headers.items()
-                            if k not in headers))
-
-        # TODO(jhylton): Should this be redesigned to handle
-        # persistent connections?
-
-        # We want to make an HTTP/1.1 request, but the addinfourl
-        # class isn't prepared to deal with a persistent connection.
-        # It will try to read all remaining data from the socket,
-        # which will block while the server waits for the next request.
-        # So make sure the connection gets closed after the (only)
-        # request.
-        headers["Connection"] = "close"
-        headers = dict((name.title(), val) for name, val in headers.items())
-
-        if req._tunnel_host:
-            tunnel_headers = {}
-            proxy_auth_hdr = "Proxy-Authorization"
-            if proxy_auth_hdr in headers:
-                tunnel_headers[proxy_auth_hdr] = headers[proxy_auth_hdr]
-                # Proxy-Authorization should not be sent to origin
-                # server.
-                del headers[proxy_auth_hdr]
-            h.set_tunnel(req._tunnel_host, headers=tunnel_headers)
-
-        try:
-            h.request(req.get_method(), req.selector, req.data, headers)
-        except socket.error as err: # timeout error
-            h.close()
-            raise URLError(err)
-        else:
-            r = h.getresponse()
-            # If the server does not send us a 'Connection: close' header,
-            # HTTPConnection assumes the socket should be left open. Manually
-            # mark the socket to be closed when this response object goes away.
-            if h.sock:
-                h.sock.close()
-                h.sock = None
-
-
-        r.url = req.get_full_url()
-        # This line replaces the .msg attribute of the HTTPResponse
-        # with .headers, because urllib clients expect the response to
-        # have the reason in .msg.  It would be good to mark this
-        # attribute is deprecated and get then to use info() or
-        # .headers.
-        r.msg = r.reason
-        return r
-
-
-class HTTPHandler(AbstractHTTPHandler):
-
-    def http_open(self, req):
-        return self.do_open(http_client.HTTPConnection, req)
-
-    http_request = AbstractHTTPHandler.do_request_
-
-if hasattr(http_client, 'HTTPSConnection'):
-
-    class HTTPSHandler(AbstractHTTPHandler):
-
-        def __init__(self, debuglevel=0, context=None, check_hostname=None):
-            AbstractHTTPHandler.__init__(self, debuglevel)
-            self._context = context
-            self._check_hostname = check_hostname
-
-        def https_open(self, req):
-            return self.do_open(http_client.HTTPSConnection, req,
-                context=self._context, check_hostname=self._check_hostname)
-
-        https_request = AbstractHTTPHandler.do_request_
-
-    __all__.append('HTTPSHandler')
-
-class HTTPCookieProcessor(BaseHandler):
-    def __init__(self, cookiejar=None):
-        import future.backports.http.cookiejar as http_cookiejar
-        if cookiejar is None:
-            cookiejar = http_cookiejar.CookieJar()
-        self.cookiejar = cookiejar
-
-    def http_request(self, request):
-        self.cookiejar.add_cookie_header(request)
-        return request
-
-    def http_response(self, request, response):
-        self.cookiejar.extract_cookies(response, request)
-        return response
-
-    https_request = http_request
-    https_response = http_response
-
-class UnknownHandler(BaseHandler):
-    def unknown_open(self, req):
-        type = req.type
-        raise URLError('unknown url type: %s' % type)
-
-def parse_keqv_list(l):
-    """Parse list of key=value strings where keys are not duplicated."""
-    parsed = {}
-    for elt in l:
-        k, v = elt.split('=', 1)
-        if v[0] == '"' and v[-1] == '"':
-            v = v[1:-1]
-        parsed[k] = v
-    return parsed
-
-def parse_http_list(s):
-    """Parse lists as described by RFC 2068 Section 2.
-
-    In particular, parse comma-separated lists where the elements of
-    the list may include quoted-strings.  A quoted-string could
-    contain a comma.  A non-quoted string could have quotes in the
-    middle.  Neither commas nor quotes count if they are escaped.
-    Only double-quotes count, not single-quotes.
-    """
-    res = []
-    part = ''
-
-    escape = quote = False
-    for cur in s:
-        if escape:
-            part += cur
-            escape = False
-            continue
-        if quote:
-            if cur == '\\':
-                escape = True
-                continue
-            elif cur == '"':
-                quote = False
-            part += cur
-            continue
-
-        if cur == ',':
-            res.append(part)
-            part = ''
-            continue
-
-        if cur == '"':
-            quote = True
-
-        part += cur
-
-    # append last part
-    if part:
-        res.append(part)
-
-    return [part.strip() for part in res]
-
-class FileHandler(BaseHandler):
-    # Use local file or FTP depending on form of URL
-    def file_open(self, req):
-        url = req.selector
-        if url[:2] == '//' and url[2:3] != '/' and (req.host and
-                req.host != 'localhost'):
-            if not req.host is self.get_names():
-                raise URLError("file:// scheme is supported only on localhost")
-        else:
-            return self.open_local_file(req)
-
-    # names for the localhost
-    names = None
-    def get_names(self):
-        if FileHandler.names is None:
-            try:
-                FileHandler.names = tuple(
-                    socket.gethostbyname_ex('localhost')[2] +
-                    socket.gethostbyname_ex(socket.gethostname())[2])
-            except socket.gaierror:
-                FileHandler.names = (socket.gethostbyname('localhost'),)
-        return FileHandler.names
-
-    # not entirely sure what the rules are here
-    def open_local_file(self, req):
-        import future.backports.email.utils as email_utils
-        import mimetypes
-        host = req.host
-        filename = req.selector
-        localfile = url2pathname(filename)
-        try:
-            stats = os.stat(localfile)
-            size = stats.st_size
-            modified = email_utils.formatdate(stats.st_mtime, usegmt=True)
-            mtype = mimetypes.guess_type(filename)[0]
-            headers = email.message_from_string(
-                'Content-type: %s\nContent-length: %d\nLast-modified: %s\n' %
-                (mtype or 'text/plain', size, modified))
-            if host:
-                host, port = splitport(host)
-            if not host or \
-                (not port and _safe_gethostbyname(host) in self.get_names()):
-                if host:
-                    origurl = 'file://' + host + filename
-                else:
-                    origurl = 'file://' + filename
-                return addinfourl(open(localfile, 'rb'), headers, origurl)
-        except OSError as exp:
-            # users shouldn't expect OSErrors coming from urlopen()
-            raise URLError(exp)
-        raise URLError('file not on local host')
-
-def _safe_gethostbyname(host):
-    try:
-        return socket.gethostbyname(host)
-    except socket.gaierror:
-        return None
-
-class FTPHandler(BaseHandler):
-    def ftp_open(self, req):
-        import ftplib
-        import mimetypes
-        host = req.host
-        if not host:
-            raise URLError('ftp error: no host given')
-        host, port = splitport(host)
-        if port is None:
-            port = ftplib.FTP_PORT
-        else:
-            port = int(port)
-
-        # username/password handling
-        user, host = splituser(host)
-        if user:
-            user, passwd = splitpasswd(user)
-        else:
-            passwd = None
-        host = unquote(host)
-        user = user or ''
-        passwd = passwd or ''
-
-        try:
-            host = socket.gethostbyname(host)
-        except socket.error as msg:
-            raise URLError(msg)
-        path, attrs = splitattr(req.selector)
-        dirs = path.split('/')
-        dirs = list(map(unquote, dirs))
-        dirs, file = dirs[:-1], dirs[-1]
-        if dirs and not dirs[0]:
-            dirs = dirs[1:]
-        try:
-            fw = self.connect_ftp(user, passwd, host, port, dirs, req.timeout)
-            type = file and 'I' or 'D'
-            for attr in attrs:
-                attr, value = splitvalue(attr)
-                if attr.lower() == 'type' and \
-                   value in ('a', 'A', 'i', 'I', 'd', 'D'):
-                    type = value.upper()
-            fp, retrlen = fw.retrfile(file, type)
-            headers = ""
-            mtype = mimetypes.guess_type(req.full_url)[0]
-            if mtype:
-                headers += "Content-type: %s\n" % mtype
-            if retrlen is not None and retrlen >= 0:
-                headers += "Content-length: %d\n" % retrlen
-            headers = email.message_from_string(headers)
-            return addinfourl(fp, headers, req.full_url)
-        except ftplib.all_errors as exp:
-            exc = URLError('ftp error: %r' % exp)
-            raise_with_traceback(exc)
-
-    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
-        return ftpwrapper(user, passwd, host, port, dirs, timeout,
-                          persistent=False)
-
-class CacheFTPHandler(FTPHandler):
-    # XXX would be nice to have pluggable cache strategies
-    # XXX this stuff is definitely not thread safe
-    def __init__(self):
-        self.cache = {}
-        self.timeout = {}
-        self.soonest = 0
-        self.delay = 60
-        self.max_conns = 16
-
-    def setTimeout(self, t):
-        self.delay = t
-
-    def setMaxConns(self, m):
-        self.max_conns = m
-
-    def connect_ftp(self, user, passwd, host, port, dirs, timeout):
-        key = user, host, port, '/'.join(dirs), timeout
-        if key in self.cache:
-            self.timeout[key] = time.time() + self.delay
-        else:
-            self.cache[key] = ftpwrapper(user, passwd, host, port,
-                                         dirs, timeout)
-            self.timeout[key] = time.time() + self.delay
-        self.check_cache()
-        return self.cache[key]
-
-    def check_cache(self):
-        # first check for old ones
-        t = time.time()
-        if self.soonest <= t:
-            for k, v in list(self.timeout.items()):
-                if v < t:
-                    self.cache[k].close()
-                    del self.cache[k]
-                    del self.timeout[k]
-        self.soonest = min(list(self.timeout.values()))
-
-        # then check the size
-        if len(self.cache) == self.max_conns:
-            for k, v in list(self.timeout.items()):
-                if v == self.soonest:
-                    del self.cache[k]
-                    del self.timeout[k]
-                    break
-            self.soonest = min(list(self.timeout.values()))
-
-    def clear_cache(self):
-        for conn in self.cache.values():
-            conn.close()
-        self.cache.clear()
-        self.timeout.clear()
-
-
-# Code move from the old urllib module
-
-MAXFTPCACHE = 10        # Trim the ftp cache beyond this size
-
-# Helper for non-unix systems
-if os.name == 'nt':
-    from nturl2path import url2pathname, pathname2url
-else:
-    def url2pathname(pathname):
-        """OS-specific conversion from a relative URL of the 'file' scheme
-        to a file system path; not recommended for general use."""
-        return unquote(pathname)
-
-    def pathname2url(pathname):
-        """OS-specific conversion from a file system path to a relative URL
-        of the 'file' scheme; not recommended for general use."""
-        return quote(pathname)
-
-# This really consists of two pieces:
-# (1) a class which handles opening of all sorts of URLs
-#     (plus assorted utilities etc.)
-# (2) a set of functions for parsing URLs
-# XXX Should these be separated out into different modules?
-
-
-ftpcache = {}
-class URLopener(object):
-    """Class to open URLs.
-    This is a class rather than just a subroutine because we may need
-    more than one set of global protocol-specific options.
-    Note -- this is a base class for those who don't want the
-    automatic handling of errors type 302 (relocated) and 401
-    (authorization needed)."""
-
-    __tempfiles = None
-
-    version = "Python-urllib/%s" % __version__
-
-    # Constructor
-    def __init__(self, proxies=None, **x509):
-        msg = "%(class)s style of invoking requests is deprecated. " \
-              "Use newer urlopen functions/methods" % {'class': self.__class__.__name__}
-        warnings.warn(msg, DeprecationWarning, stacklevel=3)
-        if proxies is None:
-            proxies = getproxies()
-        assert hasattr(proxies, 'keys'), "proxies must be a mapping"
-        self.proxies = proxies
-        self.key_file = x509.get('key_file')
-        self.cert_file = x509.get('cert_file')
-        self.addheaders = [('User-Agent', self.version)]
-        self.__tempfiles = []
-        self.__unlink = os.unlink # See cleanup()
-        self.tempcache = None
-        # Undocumented feature: if you assign {} to tempcache,
-        # it is used to cache files retrieved with
-        # self.retrieve().  This is not enabled by default
-        # since it does not work for changing documents (and I
-        # haven't got the logic to check expiration headers
-        # yet).
-        self.ftpcache = ftpcache
-        # Undocumented feature: you can use a different
-        # ftp cache by assigning to the .ftpcache member;
-        # in case you want logically independent URL openers
-        # XXX This is not threadsafe.  Bah.
-
-    def __del__(self):
-        self.close()
-
-    def close(self):
-        self.cleanup()
-
-    def cleanup(self):
-        # This code sometimes runs when the rest of this module
-        # has already been deleted, so it can't use any globals
-        # or import anything.
-        if self.__tempfiles:
-            for file in self.__tempfiles:
-                try:
-                    self.__unlink(file)
-                except OSError:
-                    pass
-            del self.__tempfiles[:]
-        if self.tempcache:
-            self.tempcache.clear()
-
-    def addheader(self, *args):
-        """Add a header to be used by the HTTP interface only
-        e.g. u.addheader('Accept', 'sound/basic')"""
-        self.addheaders.append(args)
-
-    # External interface
-    def open(self, fullurl, data=None):
-        """Use URLopener().open(file) instead of open(file, 'r')."""
-        fullurl = unwrap(to_bytes(fullurl))
-        fullurl = quote(fullurl, safe="%/:=&?~#+!$,;'@()*[]|")
-        if self.tempcache and fullurl in self.tempcache:
-            filename, headers = self.tempcache[fullurl]
-            fp = open(filename, 'rb')
-            return addinfourl(fp, headers, fullurl)
-        urltype, url = splittype(fullurl)
-        if not urltype:
-            urltype = 'file'
-        if urltype in self.proxies:
-            proxy = self.proxies[urltype]
-            urltype, proxyhost = splittype(proxy)
-            host, selector = splithost(proxyhost)
-            url = (host, fullurl) # Signal special case to open_*()
-        else:
-            proxy = None
-        name = 'open_' + urltype
-        self.type = urltype
-        name = name.replace('-', '_')
-        if not hasattr(self, name):
-            if proxy:
-                return self.open_unknown_proxy(proxy, fullurl, data)
-            else:
-                return self.open_unknown(fullurl, data)
-        try:
-            if data is None:
-                return getattr(self, name)(url)
-            else:
-                return getattr(self, name)(url, data)
-        except HTTPError:
-            raise
-        except socket.error as msg:
-            raise_with_traceback(IOError('socket error', msg))
-
-    def open_unknown(self, fullurl, data=None):
-        """Overridable interface to open unknown URL type."""
-        type, url = splittype(fullurl)
-        raise IOError('url error', 'unknown url type', type)
-
-    def open_unknown_proxy(self, proxy, fullurl, data=None):
-        """Overridable interface to open unknown URL type."""
-        type, url = splittype(fullurl)
-        raise IOError('url error', 'invalid proxy for %s' % type, proxy)
-
-    # External interface
-    def retrieve(self, url, filename=None, reporthook=None, data=None):
-        """retrieve(url) returns (filename, headers) for a local object
-        or (tempfilename, headers) for a remote object."""
-        url = unwrap(to_bytes(url))
-        if self.tempcache and url in self.tempcache:
-            return self.tempcache[url]
-        type, url1 = splittype(url)
-        if filename is None and (not type or type == 'file'):
-            try:
-                fp = self.open_local_file(url1)
-                hdrs = fp.info()
-                fp.close()
-                return url2pathname(splithost(url1)[1]), hdrs
-            except IOError as msg:
-                pass
-        fp = self.open(url, data)
-        try:
-            headers = fp.info()
-            if filename:
-                tfp = open(filename, 'wb')
-            else:
-                import tempfile
-                garbage, path = splittype(url)
-                garbage, path = splithost(path or "")
-                path, garbage = splitquery(path or "")
-                path, garbage = splitattr(path or "")
-                suffix = os.path.splitext(path)[1]
-                (fd, filename) = tempfile.mkstemp(suffix)
-                self.__tempfiles.append(filename)
-                tfp = os.fdopen(fd, 'wb')
-            try:
-                result = filename, headers
-                if self.tempcache is not None:
-                    self.tempcache[url] = result
-                bs = 1024*8
-                size = -1
-                read = 0
-                blocknum = 0
-                if "content-length" in headers:
-                    size = int(headers["Content-Length"])
-                if reporthook:
-                    reporthook(blocknum, bs, size)
-                while 1:
-                    block = fp.read(bs)
-                    if not block:
-                        break
-                    read += len(block)
-                    tfp.write(block)
-                    blocknum += 1
-                    if reporthook:
-                        reporthook(blocknum, bs, size)
-            finally:
-                tfp.close()
-        finally:
-            fp.close()
-
-        # raise exception if actual size does not match content-length header
-        if size >= 0 and read < size:
-            raise ContentTooShortError(
-                "retrieval incomplete: got only %i out of %i bytes"
-                % (read, size), result)
-
-        return result
-
-    # Each method named open_<type> knows how to open that type of URL
-
-    def _open_generic_http(self, connection_factory, url, data):
-        """Make an HTTP connection using connection_class.
-
-        This is an internal method that should be called from
-        open_http() or open_https().
-
-        Arguments:
-        - connection_factory should take a host name and return an
-          HTTPConnection instance.
-        - url is the url to retrieval or a host, relative-path pair.
-        - data is payload for a POST request or None.
-        """
-
-        user_passwd = None
-        proxy_passwd= None
-        if isinstance(url, str):
-            host, selector = splithost(url)
-            if host:
-                user_passwd, host = splituser(host)
-                host = unquote(host)
-            realhost = host
-        else:
-            host, selector = url
-            # check whether the proxy contains authorization information
-            proxy_passwd, host = splituser(host)
-            # now we proceed with the url we want to obtain
-            urltype, rest = splittype(selector)
-            url = rest
-            user_passwd = None
-            if urltype.lower() != 'http':
-                realhost = None
-            else:
-                realhost, rest = splithost(rest)
-                if realhost:
-                    user_passwd, realhost = splituser(realhost)
-                if user_passwd:
-                    selector = "%s://%s%s" % (urltype, realhost, rest)
-                if proxy_bypass(realhost):
-                    host = realhost
-
-        if not host: raise IOError('http error', 'no host given')
-
-        if proxy_passwd:
-            proxy_passwd = unquote(proxy_passwd)
-            proxy_auth = base64.b64encode(proxy_passwd.encode()).decode('ascii')
-        else:
-            proxy_auth = None
-
-        if user_passwd:
-            user_passwd = unquote(user_passwd)
-            auth = base64.b64encode(user_passwd.encode()).decode('ascii')
-        else:
-            auth = None
-        http_conn = connection_factory(host)
-        headers = {}
-        if proxy_auth:
-            headers["Proxy-Authorization"] = "Basic %s" % proxy_auth
-        if auth:
-            headers["Authorization"] =  "Basic %s" % auth
-        if realhost:
-            headers["Host"] = realhost
-
-        # Add Connection:close as we don't support persistent connections yet.
-        # This helps in closing the socket and avoiding ResourceWarning
-
-        headers["Connection"] = "close"
-
-        for header, value in self.addheaders:
-            headers[header] = value
-
-        if data is not None:
-            headers["Content-Type"] = "application/x-www-form-urlencoded"
-            http_conn.request("POST", selector, data, headers)
-        else:
-            http_conn.request("GET", selector, headers=headers)
-
-        try:
-            response = http_conn.getresponse()
-        except http_client.BadStatusLine:
-            # something went wrong with the HTTP status line
-            raise URLError("http protocol error: bad status line")
-
-        # According to RFC 2616, "2xx" code indicates that the client's
-        # request was successfully received, understood, and accepted.
-        if 200 <= response.status < 300:
-            return addinfourl(response, response.msg, "http:" + url,
-                              response.status)
-        else:
-            return self.http_error(
-                url, response.fp,
-                response.status, response.reason, response.msg, data)
-
-    def open_http(self, url, data=None):
-        """Use HTTP protocol."""
-        return self._open_generic_http(http_client.HTTPConnection, url, data)
-
-    def http_error(self, url, fp, errcode, errmsg, headers, data=None):
-        """Handle http errors.
-
-        Derived class can override this, or provide specific handlers
-        named http_error_DDD where DDD is the 3-digit error code."""
-        # First check if there's a specific handler for this error
-        name = 'http_error_%d' % errcode
-        if hasattr(self, name):
-            method = getattr(self, name)
-            if data is None:
-                result = method(url, fp, errcode, errmsg, headers)
-            else:
-                result = method(url, fp, errcode, errmsg, headers, data)
-            if result: return result
-        return self.http_error_default(url, fp, errcode, errmsg, headers)
-
-    def http_error_default(self, url, fp, errcode, errmsg, headers):
-        """Default error handler: close the connection and raise IOError."""
-        fp.close()
-        raise HTTPError(url, errcode, errmsg, headers, None)
-
-    if _have_ssl:
-        def _https_connection(self, host):
-            return http_client.HTTPSConnection(host,
-                                           key_file=self.key_file,
-                                           cert_file=self.cert_file)
-
-        def open_https(self, url, data=None):
-            """Use HTTPS protocol."""
-            return self._open_generic_http(self._https_connection, url, data)
-
-    def open_file(self, url):
-        """Use local file or FTP depending on form of URL."""
-        if not isinstance(url, str):
-            raise URLError('file error: proxy support for file protocol currently not implemented')
-        if url[:2] == '//' and url[2:3] != '/' and url[2:12].lower() != 'localhost/':
-            raise ValueError("file:// scheme is supported only on localhost")
-        else:
-            return self.open_local_file(url)
-
-    def open_local_file(self, url):
-        """Use local file."""
-        import future.backports.email.utils as email_utils
-        import mimetypes
-        host, file = splithost(url)
-        localname = url2pathname(file)
-        try:
-            stats = os.stat(localname)
-        except OSError as e:
-            raise URLError(e.strerror, e.filename)
-        size = stats.st_size
-        modified = email_utils.formatdate(stats.st_mtime, usegmt=True)
-        mtype = mimetypes.guess_type(url)[0]
-        headers = email.message_from_string(
-            'Content-Type: %s\nContent-Length: %d\nLast-modified: %s\n' %
-            (mtype or 'text/plain', size, modified))
-        if not host:
-            urlfile = file
-            if file[:1] == '/':
-                urlfile = 'file://' + file
-            return addinfourl(open(localname, 'rb'), headers, urlfile)
-        host, port = splitport(host)
-        if (not port
-           and socket.gethostbyname(host) in ((localhost(),) + thishost())):
-            urlfile = file
-            if file[:1] == '/':
-                urlfile = 'file://' + file
-            elif file[:2] == './':
-                raise ValueError("local file url may start with / or file:. Unknown url of type: %s" % url)
-            return addinfourl(open(localname, 'rb'), headers, urlfile)
-        raise URLError('local file error: not on local host')
-
-    def open_ftp(self, url):
-        """Use FTP protocol."""
-        if not isinstance(url, str):
-            raise URLError('ftp error: proxy support for ftp protocol currently not implemented')
-        import mimetypes
-        host, path = splithost(url)
-        if not host: raise URLError('ftp error: no host given')
-        host, port = splitport(host)
-        user, host = splituser(host)
-        if user: user, passwd = splitpasswd(user)
-        else: passwd = None
-        host = unquote(host)
-        user = unquote(user or '')
-        passwd = unquote(passwd or '')
-        host = socket.gethostbyname(host)
-        if not port:
-            import ftplib
-            port = ftplib.FTP_PORT
-        else:
-            port = int(port)
-        path, attrs = splitattr(path)
-        path = unquote(path)
-        dirs = path.split('/')
-        dirs, file = dirs[:-1], dirs[-1]
-        if dirs and not dirs[0]: dirs = dirs[1:]
-        if dirs and not dirs[0]: dirs[0] = '/'
-        key = user, host, port, '/'.join(dirs)
-        # XXX thread unsafe!
-        if len(self.ftpcache) > MAXFTPCACHE:
-            # Prune the cache, rather arbitrarily
-            for k in self.ftpcache.keys():
-                if k != key:
-                    v = self.ftpcache[k]
-                    del self.ftpcache[k]
-                    v.close()
-        try:
-            if key not in self.ftpcache:
-                self.ftpcache[key] = \
-                    ftpwrapper(user, passwd, host, port, dirs)
-            if not file: type = 'D'
-            else: type = 'I'
-            for attr in attrs:
-                attr, value = splitvalue(attr)
-                if attr.lower() == 'type' and \
-                   value in ('a', 'A', 'i', 'I', 'd', 'D'):
-                    type = value.upper()
-            (fp, retrlen) = self.ftpcache[key].retrfile(file, type)
-            mtype = mimetypes.guess_type("ftp:" + url)[0]
-            headers = ""
-            if mtype:
-                headers += "Content-Type: %s\n" % mtype
-            if retrlen is not None and retrlen >= 0:
-                headers += "Content-Length: %d\n" % retrlen
-            headers = email.message_from_string(headers)
-            return addinfourl(fp, headers, "ftp:" + url)
-        except ftperrors() as exp:
-            raise_with_traceback(URLError('ftp error %r' % exp))
-
-    def open_data(self, url, data=None):
-        """Use "data" URL."""
-        if not isinstance(url, str):
-            raise URLError('data error: proxy support for data protocol currently not implemented')
-        # ignore POSTed data
-        #
-        # syntax of data URLs:
-        # dataurl   := "data:" [ mediatype ] [ ";base64" ] "," data
-        # mediatype := [ type "/" subtype ] *( ";" parameter )
-        # data      := *urlchar
-        # parameter := attribute "=" value
-        try:
-            [type, data] = url.split(',', 1)
-        except ValueError:
-            raise IOError('data error', 'bad data URL')
-        if not type:
-            type = 'text/plain;charset=US-ASCII'
-        semi = type.rfind(';')
-        if semi >= 0 and '=' not in type[semi:]:
-            encoding = type[semi+1:]
-            type = type[:semi]
-        else:
-            encoding = ''
-        msg = []
-        msg.append('Date: %s'%time.strftime('%a, %d %b %Y %H:%M:%S GMT',
-                                            time.gmtime(time.time())))
-        msg.append('Content-type: %s' % type)
-        if encoding == 'base64':
-            # XXX is this encoding/decoding ok?
-            data = base64.decodebytes(data.encode('ascii')).decode('latin-1')
-        else:
-            data = unquote(data)
-        msg.append('Content-Length: %d' % len(data))
-        msg.append('')
-        msg.append(data)
-        msg = '\n'.join(msg)
-        headers = email.message_from_string(msg)
-        f = io.StringIO(msg)
-        #f.fileno = None     # needed for addinfourl
-        return addinfourl(f, headers, url)
-
-
-class FancyURLopener(URLopener):
-    """Derived class with handlers for errors we can handle (perhaps)."""
-
-    def __init__(self, *args, **kwargs):
-        URLopener.__init__(self, *args, **kwargs)
-        self.auth_cache = {}
-        self.tries = 0
-        self.maxtries = 10
-
-    def http_error_default(self, url, fp, errcode, errmsg, headers):
-        """Default error handling -- don't raise an exception."""
-        return addinfourl(fp, headers, "http:" + url, errcode)
-
-    def http_error_302(self, url, fp, errcode, errmsg, headers, data=None):
-        """Error 302 -- relocated (temporarily)."""
-        self.tries += 1
-        if self.maxtries and self.tries >= self.maxtries:
-            if hasattr(self, "http_error_500"):
-                meth = self.http_error_500
-            else:
-                meth = self.http_error_default
-            self.tries = 0
-            return meth(url, fp, 500,
-                        "Internal Server Error: Redirect Recursion", headers)
-        result = self.redirect_internal(url, fp, errcode, errmsg, headers,
-                                        data)
-        self.tries = 0
-        return result
-
-    def redirect_internal(self, url, fp, errcode, errmsg, headers, data):
-        if 'location' in headers:
-            newurl = headers['location']
-        elif 'uri' in headers:
-            newurl = headers['uri']
-        else:
-            return
-        fp.close()
-
-        # In case the server sent a relative URL, join with original:
-        newurl = urljoin(self.type + ":" + url, newurl)
-
-        urlparts = urlparse(newurl)
-
-        # For security reasons, we don't allow redirection to anything other
-        # than http, https and ftp.
-
-        # We are using newer HTTPError with older redirect_internal method
-        # This older method will get deprecated in 3.3
-
-        if urlparts.scheme not in ('http', 'https', 'ftp', ''):
-            raise HTTPError(newurl, errcode,
-                            errmsg +
-                            " Redirection to url '%s' is not allowed." % newurl,
-                            headers, fp)
-
-        return self.open(newurl)
-
-    def http_error_301(self, url, fp, errcode, errmsg, headers, data=None):
-        """Error 301 -- also relocated (permanently)."""
-        return self.http_error_302(url, fp, errcode, errmsg, headers, data)
-
-    def http_error_303(self, url, fp, errcode, errmsg, headers, data=None):
-        """Error 303 -- also relocated (essentially identical to 302)."""
-        return self.http_error_302(url, fp, errcode, errmsg, headers, data)
-
-    def http_error_307(self, url, fp, errcode, errmsg, headers, data=None):
-        """Error 307 -- relocated, but turn POST into error."""
-        if data is None:
-            return self.http_error_302(url, fp, errcode, errmsg, headers, data)
-        else:
-            return self.http_error_default(url, fp, errcode, errmsg, headers)
-
-    def http_error_401(self, url, fp, errcode, errmsg, headers, data=None,
-            retry=False):
-        """Error 401 -- authentication required.
-        This function supports Basic authentication only."""
-        if 'www-authenticate' not in headers:
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        stuff = headers['www-authenticate']
-        match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
-        if not match:
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        scheme, realm = match.groups()
-        if scheme.lower() != 'basic':
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        if not retry:
-            URLopener.http_error_default(self, url, fp, errcode, errmsg,
-                    headers)
-        name = 'retry_' + self.type + '_basic_auth'
-        if data is None:
-            return getattr(self,name)(url, realm)
-        else:
-            return getattr(self,name)(url, realm, data)
-
-    def http_error_407(self, url, fp, errcode, errmsg, headers, data=None,
-            retry=False):
-        """Error 407 -- proxy authentication required.
-        This function supports Basic authentication only."""
-        if 'proxy-authenticate' not in headers:
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        stuff = headers['proxy-authenticate']
-        match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
-        if not match:
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        scheme, realm = match.groups()
-        if scheme.lower() != 'basic':
-            URLopener.http_error_default(self, url, fp,
-                                         errcode, errmsg, headers)
-        if not retry:
-            URLopener.http_error_default(self, url, fp, errcode, errmsg,
-                    headers)
-        name = 'retry_proxy_' + self.type + '_basic_auth'
-        if data is None:
-            return getattr(self,name)(url, realm)
-        else:
-            return getattr(self,name)(url, realm, data)
-
-    def retry_proxy_http_basic_auth(self, url, realm, data=None):
-        host, selector = splithost(url)
-        newurl = 'http://' + host + selector
-        proxy = self.proxies['http']
-        urltype, proxyhost = splittype(proxy)
-        proxyhost, proxyselector = splithost(proxyhost)
-        i = proxyhost.find('@') + 1
-        proxyhost = proxyhost[i:]
-        user, passwd = self.get_user_passwd(proxyhost, realm, i)
-        if not (user or passwd): return None
-        proxyhost = "%s:%s@%s" % (quote(user, safe=''),
-                                  quote(passwd, safe=''), proxyhost)
-        self.proxies['http'] = 'http://' + proxyhost + proxyselector
-        if data is None:
-            return self.open(newurl)
-        else:
-            return self.open(newurl, data)
-
-    def retry_proxy_https_basic_auth(self, url, realm, data=None):
-        host, selector = splithost(url)
-        newurl = 'https://' + host + selector
-        proxy = self.proxies['https']
-        urltype, proxyhost = splittype(proxy)
-        proxyhost, proxyselector = splithost(proxyhost)
-        i = proxyhost.find('@') + 1
-        proxyhost = proxyhost[i:]
-        user, passwd = self.get_user_passwd(proxyhost, realm, i)
-        if not (user or passwd): return None
-        proxyhost = "%s:%s@%s" % (quote(user, safe=''),
-                                  quote(passwd, safe=''), proxyhost)
-        self.proxies['https'] = 'https://' + proxyhost + proxyselector
-        if data is None:
-            return self.open(newurl)
-        else:
-            return self.open(newurl, data)
-
-    def retry_http_basic_auth(self, url, realm, data=None):
-        host, selector = splithost(url)
-        i = host.find('@') + 1
-        host = host[i:]
-        user, passwd = self.get_user_passwd(host, realm, i)
-        if not (user or passwd): return None
-        host = "%s:%s@%s" % (quote(user, safe=''),
-                             quote(passwd, safe=''), host)
-        newurl = 'http://' + host + selector
-        if data is None:
-            return self.open(newurl)
-        else:
-            return self.open(newurl, data)
-
-    def retry_https_basic_auth(self, url, realm, data=None):
-        host, selector = splithost(url)
-        i = host.find('@') + 1
-        host = host[i:]
-        user, passwd = self.get_user_passwd(host, realm, i)
-        if not (user or passwd): return None
-        host = "%s:%s@%s" % (quote(user, safe=''),
-                             quote(passwd, safe=''), host)
-        newurl = 'https://' + host + selector
-        if data is None:
-            return self.open(newurl)
-        else:
-            return self.open(newurl, data)
-
-    def get_user_passwd(self, host, realm, clear_cache=0):
-        key = realm + '@' + host.lower()
-        if key in self.auth_cache:
-            if clear_cache:
-                del self.auth_cache[key]
-            else:
-                return self.auth_cache[key]
-        user, passwd = self.prompt_user_passwd(host, realm)
-        if user or passwd: self.auth_cache[key] = (user, passwd)
-        return user, passwd
-
-    def prompt_user_passwd(self, host, realm):
-        """Override this in a GUI environment!"""
-        import getpass
-        try:
-            user = input("Enter username for %s at %s: " % (realm, host))
-            passwd = getpass.getpass("Enter password for %s in %s at %s: " %
-                (user, realm, host))
-            return user, passwd
-        except KeyboardInterrupt:
-            print()
-            return None, None
-
-
-# Utility functions
-
-_localhost = None
-def localhost():
-    """Return the IP address of the magic hostname 'localhost'."""
-    global _localhost
-    if _localhost is None:
-        _localhost = socket.gethostbyname('localhost')
-    return _localhost
-
-_thishost = None
-def thishost():
-    """Return the IP addresses of the current host."""
-    global _thishost
-    if _thishost is None:
-        try:
-            _thishost = tuple(socket.gethostbyname_ex(socket.gethostname())[2])
-        except socket.gaierror:
-            _thishost = tuple(socket.gethostbyname_ex('localhost')[2])
-    return _thishost
-
-_ftperrors = None
-def ftperrors():
-    """Return the set of errors raised by the FTP class."""
-    global _ftperrors
-    if _ftperrors is None:
-        import ftplib
-        _ftperrors = ftplib.all_errors
-    return _ftperrors
-
-_noheaders = None
-def noheaders():
-    """Return an empty email Message object."""
-    global _noheaders
-    if _noheaders is None:
-        _noheaders = email.message_from_string("")
-    return _noheaders
-
-
-# Utility classes
-
-class ftpwrapper(object):
-    """Class used by open_ftp() for cache of open FTP connections."""
-
-    def __init__(self, user, passwd, host, port, dirs, timeout=None,
-                 persistent=True):
-        self.user = user
-        self.passwd = passwd
-        self.host = host
-        self.port = port
-        self.dirs = dirs
-        self.timeout = timeout
-        self.refcount = 0
-        self.keepalive = persistent
-        self.init()
-
-    def init(self):
-        import ftplib
-        self.busy = 0
-        self.ftp = ftplib.FTP()
-        self.ftp.connect(self.host, self.port, self.timeout)
-        self.ftp.login(self.user, self.passwd)
-        _target = '/'.join(self.dirs)
-        self.ftp.cwd(_target)
-
-    def retrfile(self, file, type):
-        import ftplib
-        self.endtransfer()
-        if type in ('d', 'D'): cmd = 'TYPE A'; isdir = 1
-        else: cmd = 'TYPE ' + type; isdir = 0
-        try:
-            self.ftp.voidcmd(cmd)
-        except ftplib.all_errors:
-            self.init()
-            self.ftp.voidcmd(cmd)
-        conn = None
-        if file and not isdir:
-            # Try to retrieve as a file
-            try:
-                cmd = 'RETR ' + file
-                conn, retrlen = self.ftp.ntransfercmd(cmd)
-            except ftplib.error_perm as reason:
-                if str(reason)[:3] != '550':
-                    raise_with_traceback(URLError('ftp error: %r' % reason))
-        if not conn:
-            # Set transfer mode to ASCII!
-            self.ftp.voidcmd('TYPE A')
-            # Try a directory listing. Verify that directory exists.
-            if file:
-                pwd = self.ftp.pwd()
-                try:
-                    try:
-                        self.ftp.cwd(file)
-                    except ftplib.error_perm as reason:
-                        ### Was:
-                        # raise URLError('ftp error: %r' % reason) from reason
-                        exc = URLError('ftp error: %r' % reason)
-                        exc.__cause__ = reason
-                        raise exc
-                finally:
-                    self.ftp.cwd(pwd)
-                cmd = 'LIST ' + file
-            else:
-                cmd = 'LIST'
-            conn, retrlen = self.ftp.ntransfercmd(cmd)
-        self.busy = 1
-
-        ftpobj = addclosehook(conn.makefile('rb'), self.file_close)
-        self.refcount += 1
-        conn.close()
-        # Pass back both a suitably decorated object and a retrieval length
-        return (ftpobj, retrlen)
-
-    def endtransfer(self):
-        self.busy = 0
-
-    def close(self):
-        self.keepalive = False
-        if self.refcount <= 0:
-            self.real_close()
-
-    def file_close(self):
-        self.endtransfer()
-        self.refcount -= 1
-        if self.refcount <= 0 and not self.keepalive:
-            self.real_close()
-
-    def real_close(self):
-        self.endtransfer()
-        try:
-            self.ftp.close()
-        except ftperrors():
-            pass
-
-# Proxy handling
-def getproxies_environment():
-    """Return a dictionary of scheme -> proxy server URL mappings.
-
-    Scan the environment for variables named <scheme>_proxy;
-    this seems to be the standard convention.  If you need a
-    different way, you can pass a proxies dictionary to the
-    [Fancy]URLopener constructor.
-
-    """
-    proxies = {}
-    for name, value in os.environ.items():
-        name = name.lower()
-        if value and name[-6:] == '_proxy':
-            proxies[name[:-6]] = value
-    return proxies
-
-def proxy_bypass_environment(host):
-    """Test if proxies should not be used for a particular host.
-
-    Checks the environment for a variable named no_proxy, which should
-    be a list of DNS suffixes separated by commas, or '*' for all hosts.
-    """
-    no_proxy = os.environ.get('no_proxy', '') or os.environ.get('NO_PROXY', '')
-    # '*' is special case for always bypass
-    if no_proxy == '*':
-        return 1
-    # strip port off host
-    hostonly, port = splitport(host)
-    # check if the host ends with any of the DNS suffixes
-    no_proxy_list = [proxy.strip() for proxy in no_proxy.split(',')]
-    for name in no_proxy_list:
-        if name and (hostonly.endswith(name) or host.endswith(name)):
-            return 1
-    # otherwise, don't bypass
-    return 0
-
-
-# This code tests an OSX specific data structure but is testable on all
-# platforms
-def _proxy_bypass_macosx_sysconf(host, proxy_settings):
-    """
-    Return True iff this host shouldn't be accessed using a proxy
-
-    This function uses the MacOSX framework SystemConfiguration
-    to fetch the proxy information.
-
-    proxy_settings come from _scproxy._get_proxy_settings or get mocked ie:
-    { 'exclude_simple': bool,
-      'exceptions': ['foo.bar', '*.bar.com', '127.0.0.1', '10.1', '10.0/16']
-    }
-    """
-    from fnmatch import fnmatch
-
-    hostonly, port = splitport(host)
-
-    def ip2num(ipAddr):
-        parts = ipAddr.split('.')
-        parts = list(map(int, parts))
-        if len(parts) != 4:
-            parts = (parts + [0, 0, 0, 0])[:4]
-        return (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8) | parts[3]
-
-    # Check for simple host names:
-    if '.' not in host:
-        if proxy_settings['exclude_simple']:
-            return True
-
-    hostIP = None
-
-    for value in proxy_settings.get('exceptions', ()):
-        # Items in the list are strings like these: *.local, 169.254/16
-        if not value: continue
-
-        m = re.match(r"(\d+(?:\.\d+)*)(/\d+)?", value)
-        if m is not None:
-            if hostIP is None:
-                try:
-                    hostIP = socket.gethostbyname(hostonly)
-                    hostIP = ip2num(hostIP)
-                except socket.error:
-                    continue
-
-            base = ip2num(m.group(1))
-            mask = m.group(2)
-            if mask is None:
-                mask = 8 * (m.group(1).count('.') + 1)
-            else:
-                mask = int(mask[1:])
-            mask = 32 - mask
-
-            if (hostIP >> mask) == (base >> mask):
-                return True
-
-        elif fnmatch(host, value):
-            return True
-
-    return False
-
-
-if sys.platform == 'darwin':
-    from _scproxy import _get_proxy_settings, _get_proxies
-
-    def proxy_bypass_macosx_sysconf(host):
-        proxy_settings = _get_proxy_settings()
-        return _proxy_bypass_macosx_sysconf(host, proxy_settings)
-
-    def getproxies_macosx_sysconf():
-        """Return a dictionary of scheme -> proxy server URL mappings.
-
-        This function uses the MacOSX framework SystemConfiguration
-        to fetch the proxy information.
-        """
-        return _get_proxies()
-
-
-
-    def proxy_bypass(host):
-        if getproxies_environment():
-            return proxy_bypass_environment(host)
-        else:
-            return proxy_bypass_macosx_sysconf(host)
-
-    def getproxies():
-        return getproxies_environment() or getproxies_macosx_sysconf()
-
-
-elif os.name == 'nt':
-    def getproxies_registry():
-        """Return a dictionary of scheme -> proxy server URL mappings.
-
-        Win32 uses the registry to store proxies.
-
-        """
-        proxies = {}
-        try:
-            import winreg
-        except ImportError:
-            # Std module, so should be around - but you never know!
-            return proxies
-        try:
-            internetSettings = winreg.OpenKey(winreg.HKEY_CURRENT_USER,
-                r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
-            proxyEnable = winreg.QueryValueEx(internetSettings,
-                                               'ProxyEnable')[0]
-            if proxyEnable:
-                # Returned as Unicode but problems if not converted to ASCII
-                proxyServer = str(winreg.QueryValueEx(internetSettings,
-                                                       'ProxyServer')[0])
-                if '=' in proxyServer:
-                    # Per-protocol settings
-                    for p in proxyServer.split(';'):
-                        protocol, address = p.split('=', 1)
-                        # See if address has a type:// prefix
-                        if not re.match('^([^/:]+)://', address):
-                            address = '%s://%s' % (protocol, address)
-                        proxies[protocol] = address
-                else:
-                    # Use one setting for all protocols
-                    if proxyServer[:5] == 'http:':
-                        proxies['http'] = proxyServer
-                    else:
-                        proxies['http'] = 'http://%s' % proxyServer
-                        proxies['https'] = 'https://%s' % proxyServer
-                        proxies['ftp'] = 'ftp://%s' % proxyServer
-            internetSettings.Close()
-        except (WindowsError, ValueError, TypeError):
-            # Either registry key not found etc, or the value in an
-            # unexpected format.
-            # proxies already set up to be empty so nothing to do
-            pass
-        return proxies
-
-    def getproxies():
-        """Return a dictionary of scheme -> proxy server URL mappings.
-
-        Returns settings gathered from the environment, if specified,
-        or the registry.
-
-        """
-        return getproxies_environment() or getproxies_registry()
-
-    def proxy_bypass_registry(host):
-        try:
-            import winreg
-        except ImportError:
-            # Std modules, so should be around - but you never know!
-            return 0
-        try:
-            internetSettings = winreg.OpenKey(winreg.HKEY_CURRENT_USER,
-                r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
-            proxyEnable = winreg.QueryValueEx(internetSettings,
-                                               'ProxyEnable')[0]
-            proxyOverride = str(winreg.QueryValueEx(internetSettings,
-                                                     'ProxyOverride')[0])
-            # ^^^^ Returned as Unicode but problems if not converted to ASCII
-        except WindowsError:
-            return 0
-        if not proxyEnable or not proxyOverride:
-            return 0
-        # try to make a host list from name and IP address.
-        rawHost, port = splitport(host)
-        host = [rawHost]
-        try:
-            addr = socket.gethostbyname(rawHost)
-            if addr != rawHost:
-                host.append(addr)
-        except socket.error:
-            pass
-        try:
-            fqdn = socket.getfqdn(rawHost)
-            if fqdn != rawHost:
-                host.append(fqdn)
-        except socket.error:
-            pass
-        # make a check value list from the registry entry: replace the
-        # '<local>' string by the localhost entry and the corresponding
-        # canonical entry.
-        proxyOverride = proxyOverride.split(';')
-        # now check if we match one of the registry values.
-        for test in proxyOverride:
-            if test == '<local>':
-                if '.' not in rawHost:
-                    return 1
-            test = test.replace(".", r"\.")     # mask dots
-            test = test.replace("*", r".*")     # change glob sequence
-            test = test.replace("?", r".")      # change glob char
-            for val in host:
-                if re.match(test, val, re.I):
-                    return 1
-        return 0
-
-    def proxy_bypass(host):
-        """Return a dictionary of scheme -> proxy server URL mappings.
-
-        Returns settings gathered from the environment, if specified,
-        or the registry.
-
-        """
-        if getproxies_environment():
-            return proxy_bypass_environment(host)
-        else:
-            return proxy_bypass_registry(host)
-
-else:
-    # By default use environment variables
-    getproxies = getproxies_environment
-    proxy_bypass = proxy_bypass_environment