docs: def log(self, source_id, page=None, per_page=None):
          """ Get the log for a specific Managed Source.
  
              Uses API documented at http://dev.datasift.com/docs/api/rest-api/endpoints/sourcelog
  
              :param source_id: target Source ID
              :type source_id: str
              :param page: (optional) page number for pagination
              :type page: int
              :param per_page: (optional) number of items per page, default 20
              :type per_page: int
              :return: dict of REST API output with headers attached
              :rtype: :class:`~datasift.request.DictResponse`
              :raises: :class:`~datasift.exceptions.DataSiftApiException`, :class:`requests.exceptions.HTTPError`
          """
          params = {'id': source_id}
          if page:
              params['page'] = page
          if per_page:
              params['per_page'] = per_page
  
          return self.request.get('log', params=params)