code: def _build_authorization_request_url(
          self,
          response_type,
          state=None
      ):
          
          if response_type not in auth.VALID_RESPONSE_TYPES:
              message = '{} is not a valid response type.'
              raise LyftIllegalState(message.format(response_type))
  
          args = OrderedDict([
              ('scope', ' '.join(self.scopes)),
              ('state', state),
              ('response_type', response_type),
              ('client_id', self.client_id),
          ])
  
          return build_url(auth.SERVER_HOST, auth.AUTHORIZE_PATH, args)
docs: Form URL to request an auth code or access token.
          Parameters
              response_type (str)
                  Only 'code' (Authorization Code Grant) supported at this time
              state (str)
                  Optional CSRF State token to send to server.
          Returns
              (str)
                  The fully constructed authorization request URL.
          Raises
              LyftIllegalState (ApiError)
                  Raised if response_type parameter is invalid.