'Queries server to find out state of given upload.
Note that this method really just makes special case use of the
fact that the upload server always returns the current start/end
state whenever a PUT doesn\'t complete.
Returns HTTP response from sending request.
Raises ResumableUploadException if problem querying server.'

def _query_server_state(self, conn, file_length):

    put_headers = {}
    put_headers['Content-Range'] = self._build_content_range_header('*', file_length)
    put_headers['Content-Length'] = '0'
    return AWSAuthConnection.make_request(conn, 'PUT', path=self.tracker_uri_path, auth_path=self.tracker_uri_path, headers=put_headers, host=self.tracker_uri_host)
