def __init__(self, credentials, http=None,<EOL>refresh_status_codes=transport.DEFAULT_REFRESH_STATUS_CODES,<EOL>max_refresh_attempts=transport.DEFAULT_MAX_REFRESH_ATTEMPTS):
if http is None:<EOL><INDENT>http = _make_default_http()<EOL><DEDENT>self.http = http<EOL>self.credentials = credentials<EOL>self._refresh_status_codes = refresh_status_codes<EOL>self._max_refresh_attempts = max_refresh_attempts<EOL>self._request = Request(self.http)<EOL>
Args:
    credentials (google.auth.credentials.Credentials): The credentials
        to add to the request.
    http (httplib2.Http): The underlying HTTP object to
        use to make requests. If not specified, a
        :class:`httplib2.Http` instance will be constructed.
    refresh_status_codes (Sequence[int]): Which HTTP status codes
        indicate that credentials should be refreshed and the request
        should be retried.
    max_refresh_attempts (int): The maximum number of times to attempt
        to refresh the credentials and retry the request.