--- a/env/lib/python3.7/site-packages/urllib3/util/retry.py	Thu May 14 16:47:39 2020 -0400
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,453 +0,0 @@
-from __future__ import absolute_import
-import time
-import logging
-from collections import namedtuple
-from itertools import takewhile
-import email
-import re
-
-from ..exceptions import (
-    ConnectTimeoutError,
-    MaxRetryError,
-    ProtocolError,
-    ReadTimeoutError,
-    ResponseError,
-    InvalidHeader,
-    ProxyError,
-)
-from ..packages import six
-
-
-log = logging.getLogger(__name__)
-
-
-# Data structure for representing the metadata of requests that result in a retry.
-RequestHistory = namedtuple(
-    "RequestHistory", ["method", "url", "error", "status", "redirect_location"]
-)
-
-
-class Retry(object):
-    """ Retry configuration.
-
-    Each retry attempt will create a new Retry object with updated values, so
-    they can be safely reused.
-
-    Retries can be defined as a default for a pool::
-
-        retries = Retry(connect=5, read=2, redirect=5)
-        http = PoolManager(retries=retries)
-        response = http.request('GET', 'http://example.com/')
-
-    Or per-request (which overrides the default for the pool)::
-
-        response = http.request('GET', 'http://example.com/', retries=Retry(10))
-
-    Retries can be disabled by passing ``False``::
-
-        response = http.request('GET', 'http://example.com/', retries=False)
-
-    Errors will be wrapped in :class:`~urllib3.exceptions.MaxRetryError` unless
-    retries are disabled, in which case the causing exception will be raised.
-
-    :param int total:
-        Total number of retries to allow. Takes precedence over other counts.
-
-        Set to ``None`` to remove this constraint and fall back on other
-        counts. It's a good idea to set this to some sensibly-high value to
-        account for unexpected edge cases and avoid infinite retry loops.
-
-        Set to ``0`` to fail on the first retry.
-
-        Set to ``False`` to disable and imply ``raise_on_redirect=False``.
-
-    :param int connect:
-        How many connection-related errors to retry on.
-
-        These are errors raised before the request is sent to the remote server,
-        which we assume has not triggered the server to process the request.
-
-        Set to ``0`` to fail on the first retry of this type.
-
-    :param int read:
-        How many times to retry on read errors.
-
-        These errors are raised after the request was sent to the server, so the
-        request may have side-effects.
-
-        Set to ``0`` to fail on the first retry of this type.
-
-    :param int redirect:
-        How many redirects to perform. Limit this to avoid infinite redirect
-        loops.
-
-        A redirect is a HTTP response with a status code 301, 302, 303, 307 or
-        308.
-
-        Set to ``0`` to fail on the first retry of this type.
-
-        Set to ``False`` to disable and imply ``raise_on_redirect=False``.
-
-    :param int status:
-        How many times to retry on bad status codes.
-
-        These are retries made on responses, where status code matches
-        ``status_forcelist``.
-
-        Set to ``0`` to fail on the first retry of this type.
-
-    :param iterable method_whitelist:
-        Set of uppercased HTTP method verbs that we should retry on.
-
-        By default, we only retry on methods which are considered to be
-        idempotent (multiple requests with the same parameters end with the
-        same state). See :attr:`Retry.DEFAULT_METHOD_WHITELIST`.
-
-        Set to a ``False`` value to retry on any verb.
-
-    :param iterable status_forcelist:
-        A set of integer HTTP status codes that we should force a retry on.
-        A retry is initiated if the request method is in ``method_whitelist``
-        and the response status code is in ``status_forcelist``.
-
-        By default, this is disabled with ``None``.
-
-    :param float backoff_factor:
-        A backoff factor to apply between attempts after the second try
-        (most errors are resolved immediately by a second try without a
-        delay). urllib3 will sleep for::
-
-            {backoff factor} * (2 ** ({number of total retries} - 1))
-
-        seconds. If the backoff_factor is 0.1, then :func:`.sleep` will sleep
-        for [0.0s, 0.2s, 0.4s, ...] between retries. It will never be longer
-        than :attr:`Retry.BACKOFF_MAX`.
-
-        By default, backoff is disabled (set to 0).
-
-    :param bool raise_on_redirect: Whether, if the number of redirects is
-        exhausted, to raise a MaxRetryError, or to return a response with a
-        response code in the 3xx range.
-
-    :param bool raise_on_status: Similar meaning to ``raise_on_redirect``:
-        whether we should raise an exception, or return a response,
-        if status falls in ``status_forcelist`` range and retries have
-        been exhausted.
-
-    :param tuple history: The history of the request encountered during
-        each call to :meth:`~Retry.increment`. The list is in the order
-        the requests occurred. Each list item is of class :class:`RequestHistory`.
-
-    :param bool respect_retry_after_header:
-        Whether to respect Retry-After header on status codes defined as
-        :attr:`Retry.RETRY_AFTER_STATUS_CODES` or not.
-
-    :param iterable remove_headers_on_redirect:
-        Sequence of headers to remove from the request when a response
-        indicating a redirect is returned before firing off the redirected
-        request.
-    """
-
-    DEFAULT_METHOD_WHITELIST = frozenset(
-        ["HEAD", "GET", "PUT", "DELETE", "OPTIONS", "TRACE"]
-    )
-
-    RETRY_AFTER_STATUS_CODES = frozenset([413, 429, 503])
-
-    DEFAULT_REDIRECT_HEADERS_BLACKLIST = frozenset(["Authorization"])
-
-    #: Maximum backoff time.
-    BACKOFF_MAX = 120
-
-    def __init__(
-        self,
-        total=10,
-        connect=None,
-        read=None,
-        redirect=None,
-        status=None,
-        method_whitelist=DEFAULT_METHOD_WHITELIST,
-        status_forcelist=None,
-        backoff_factor=0,
-        raise_on_redirect=True,
-        raise_on_status=True,
-        history=None,
-        respect_retry_after_header=True,
-        remove_headers_on_redirect=DEFAULT_REDIRECT_HEADERS_BLACKLIST,
-    ):
-
-        self.total = total
-        self.connect = connect
-        self.read = read
-        self.status = status
-
-        if redirect is False or total is False:
-            redirect = 0
-            raise_on_redirect = False
-
-        self.redirect = redirect
-        self.status_forcelist = status_forcelist or set()
-        self.method_whitelist = method_whitelist
-        self.backoff_factor = backoff_factor
-        self.raise_on_redirect = raise_on_redirect
-        self.raise_on_status = raise_on_status
-        self.history = history or tuple()
-        self.respect_retry_after_header = respect_retry_after_header
-        self.remove_headers_on_redirect = frozenset(
-            [h.lower() for h in remove_headers_on_redirect]
-        )
-
-    def new(self, **kw):
-        params = dict(
-            total=self.total,
-            connect=self.connect,
-            read=self.read,
-            redirect=self.redirect,
-            status=self.status,
-            method_whitelist=self.method_whitelist,
-            status_forcelist=self.status_forcelist,
-            backoff_factor=self.backoff_factor,
-            raise_on_redirect=self.raise_on_redirect,
-            raise_on_status=self.raise_on_status,
-            history=self.history,
-            remove_headers_on_redirect=self.remove_headers_on_redirect,
-            respect_retry_after_header=self.respect_retry_after_header,
-        )
-        params.update(kw)
-        return type(self)(**params)
-
-    @classmethod
-    def from_int(cls, retries, redirect=True, default=None):
-        """ Backwards-compatibility for the old retries format."""
-        if retries is None:
-            retries = default if default is not None else cls.DEFAULT
-
-        if isinstance(retries, Retry):
-            return retries
-
-        redirect = bool(redirect) and None
-        new_retries = cls(retries, redirect=redirect)
-        log.debug("Converted retries value: %r -> %r", retries, new_retries)
-        return new_retries
-
-    def get_backoff_time(self):
-        """ Formula for computing the current backoff
-
-        :rtype: float
-        """
-        # We want to consider only the last consecutive errors sequence (Ignore redirects).
-        consecutive_errors_len = len(
-            list(
-                takewhile(lambda x: x.redirect_location is None, reversed(self.history))
-            )
-        )
-        if consecutive_errors_len <= 1:
-            return 0
-
-        backoff_value = self.backoff_factor * (2 ** (consecutive_errors_len - 1))
-        return min(self.BACKOFF_MAX, backoff_value)
-
-    def parse_retry_after(self, retry_after):
-        # Whitespace: https://tools.ietf.org/html/rfc7230#section-3.2.4
-        if re.match(r"^\s*[0-9]+\s*$", retry_after):
-            seconds = int(retry_after)
-        else:
-            retry_date_tuple = email.utils.parsedate(retry_after)
-            if retry_date_tuple is None:
-                raise InvalidHeader("Invalid Retry-After header: %s" % retry_after)
-            retry_date = time.mktime(retry_date_tuple)
-            seconds = retry_date - time.time()
-
-        if seconds < 0:
-            seconds = 0
-
-        return seconds
-
-    def get_retry_after(self, response):
-        """ Get the value of Retry-After in seconds. """
-
-        retry_after = response.getheader("Retry-After")
-
-        if retry_after is None:
-            return None
-
-        return self.parse_retry_after(retry_after)
-
-    def sleep_for_retry(self, response=None):
-        retry_after = self.get_retry_after(response)
-        if retry_after:
-            time.sleep(retry_after)
-            return True
-
-        return False
-
-    def _sleep_backoff(self):
-        backoff = self.get_backoff_time()
-        if backoff <= 0:
-            return
-        time.sleep(backoff)
-
-    def sleep(self, response=None):
-        """ Sleep between retry attempts.
-
-        This method will respect a server's ``Retry-After`` response header
-        and sleep the duration of the time requested. If that is not present, it
-        will use an exponential backoff. By default, the backoff factor is 0 and
-        this method will return immediately.
-        """
-
-        if self.respect_retry_after_header and response:
-            slept = self.sleep_for_retry(response)
-            if slept:
-                return
-
-        self._sleep_backoff()
-
-    def _is_connection_error(self, err):
-        """ Errors when we're fairly sure that the server did not receive the
-        request, so it should be safe to retry.
-        """
-        if isinstance(err, ProxyError):
-            err = err.original_error
-        return isinstance(err, ConnectTimeoutError)
-
-    def _is_read_error(self, err):
-        """ Errors that occur after the request has been started, so we should
-        assume that the server began processing it.
-        """
-        return isinstance(err, (ReadTimeoutError, ProtocolError))
-
-    def _is_method_retryable(self, method):
-        """ Checks if a given HTTP method should be retried upon, depending if
-        it is included on the method whitelist.
-        """
-        if self.method_whitelist and method.upper() not in self.method_whitelist:
-            return False
-
-        return True
-
-    def is_retry(self, method, status_code, has_retry_after=False):
-        """ Is this method/status code retryable? (Based on whitelists and control
-        variables such as the number of total retries to allow, whether to
-        respect the Retry-After header, whether this header is present, and
-        whether the returned status code is on the list of status codes to
-        be retried upon on the presence of the aforementioned header)
-        """
-        if not self._is_method_retryable(method):
-            return False
-
-        if self.status_forcelist and status_code in self.status_forcelist:
-            return True
-
-        return (
-            self.total
-            and self.respect_retry_after_header
-            and has_retry_after
-            and (status_code in self.RETRY_AFTER_STATUS_CODES)
-        )
-
-    def is_exhausted(self):
-        """ Are we out of retries? """
-        retry_counts = (self.total, self.connect, self.read, self.redirect, self.status)
-        retry_counts = list(filter(None, retry_counts))
-        if not retry_counts:
-            return False
-
-        return min(retry_counts) < 0
-
-    def increment(
-        self,
-        method=None,
-        url=None,
-        response=None,
-        error=None,
-        _pool=None,
-        _stacktrace=None,
-    ):
-        """ Return a new Retry object with incremented retry counters.
-
-        :param response: A response object, or None, if the server did not
-            return a response.
-        :type response: :class:`~urllib3.response.HTTPResponse`
-        :param Exception error: An error encountered during the request, or
-            None if the response was received successfully.
-
-        :return: A new ``Retry`` object.
-        """
-        if self.total is False and error:
-            # Disabled, indicate to re-raise the error.
-            raise six.reraise(type(error), error, _stacktrace)
-
-        total = self.total
-        if total is not None:
-            total -= 1
-
-        connect = self.connect
-        read = self.read
-        redirect = self.redirect
-        status_count = self.status
-        cause = "unknown"
-        status = None
-        redirect_location = None
-
-        if error and self._is_connection_error(error):
-            # Connect retry?
-            if connect is False:
-                raise six.reraise(type(error), error, _stacktrace)
-            elif connect is not None:
-                connect -= 1
-
-        elif error and self._is_read_error(error):
-            # Read retry?
-            if read is False or not self._is_method_retryable(method):
-                raise six.reraise(type(error), error, _stacktrace)
-            elif read is not None:
-                read -= 1
-
-        elif response and response.get_redirect_location():
-            # Redirect retry?
-            if redirect is not None:
-                redirect -= 1
-            cause = "too many redirects"
-            redirect_location = response.get_redirect_location()
-            status = response.status
-
-        else:
-            # Incrementing because of a server error like a 500 in
-            # status_forcelist and a the given method is in the whitelist
-            cause = ResponseError.GENERIC_ERROR
-            if response and response.status:
-                if status_count is not None:
-                    status_count -= 1
-                cause = ResponseError.SPECIFIC_ERROR.format(status_code=response.status)
-                status = response.status
-
-        history = self.history + (
-            RequestHistory(method, url, error, status, redirect_location),
-        )
-
-        new_retry = self.new(
-            total=total,
-            connect=connect,
-            read=read,
-            redirect=redirect,
-            status=status_count,
-            history=history,
-        )
-
-        if new_retry.is_exhausted():
-            raise MaxRetryError(_pool, url, error or ResponseError(cause))
-
-        log.debug("Incremented Retry for (url='%s'): %r", url, new_retry)
-
-        return new_retry
-
-    def __repr__(self):
-        return (
-            "{cls.__name__}(total={self.total}, connect={self.connect}, "
-            "read={self.read}, redirect={self.redirect}, status={self.status})"
-        ).format(cls=type(self), self=self)
-
-
-# For backwards compatibility (equivalent to pre-v1.9):
-Retry.DEFAULT = Retry(3)