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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def urlopen(self, method, url, body=None, headers=None, **kwargs):
 """Implementation of urllib3's urlopen."""

        # pylint: disable=arguments-differ
        # We use kwargs to collect additional args that we don't need to
        # introspect here. However, we do explicitly collect the two
        # positional arguments.

        # Use a kwarg for this instead of an attribute to maintain
        # thread-safety.
        _credential_refresh_attempt = kwargs.pop(
            '_credential_refresh_attempt', 0)

        if headers is None:
            headers = self.headers

        # Make a copy of the headers. They will be modified by the credentials
        # and we want to pass the original headers if we recurse.
        request_headers = headers.copy()

        self.credentials.before_request(
            self._request, method, url, request_headers)

        response = self.http.urlopen(
            method, url, body=body, headers=request_headers, **kwargs)

        # If the response indicated that the credentials needed to be
        # refreshed, then refresh the credentials and re-attempt the
        # request.
        # A stored token may expire between the time it is retrieved and
        # the time the request is made, so we may need to try twice.
        # The reason urllib3's retries aren't used is because they
        # don't allow you to modify the request headers. :/
        if (response.status in self._refresh_status_codes
                and _credential_refresh_attempt < self._max_refresh_attempts):

            _LOGGER.info(
                'Refreshing credentials due to a %s response. Attempt %s/%s.',
                response.status, _credential_refresh_attempt + 1,
                self._max_refresh_attempts)

            self.credentials.refresh(self._request)

            # Recurse. Pass in the original headers, not our modified set.
            return self.urlopen(
                method, url, body=body, headers=headers,
                _credential_refresh_attempt=_credential_refresh_attempt + 1,
                **kwargs)

        return response