code: def authorization_error_class(response):
      
      message = response.headers.get("www-authenticate")
      if message:
          error = message.replace('"', "").rsplit("=", 1)[1]
      else:
          error = response.status_code
      return _auth_error_mapping[error](response)
docs: Return an exception instance that maps to the OAuth Error.
  
      :param response: The HTTP response containing a www-authenticate error.