docs: def update(self, subscription_id, output_params, name=None):
          """ Update the name or output parameters for an existing Subscription.
  
              Uses API documented at http://dev.datasift.com/docs/api/rest-api/endpoints/pushupdate
  
              :param subscription_id: id of an existing Push Subscription.
              :type subscription_id: str
              :param output_params: new output parameters for the subscription, see dev.datasift.com
              :type output_params: dict
              :param name: optional new name for the Subscription
              :type name: str
              :returns: dict with extra response data
              :rtype: :class:`~datasift.request.DictResponse`
              :raises: :class:`~datasift.exceptions.DataSiftApiException`, :class:`requests.exceptions.HTTPError`
          """
          params = {'id': subscription_id, 'output_params': output_params}
          if name:
              params['name'] = name
          return self.request.post('update', params)