code: def get_table_schema(self, dataset, table, project_id=None):
          
          project_id = self._get_project_id(project_id)
  
          try:    
              result = self.bigquery.tables().get(
                  projectId=project_id,
                  tableId=table,
                  datasetId=dataset).execute(num_retries=self.num_retries)
          except HttpError as e:
              if int(e.resp['status']) == 404:
                  logger.warn('Table %s.%s does not exist', dataset, table)
                  return None
              raise
  
          return result['schema']['fields']
docs: Return the table schema.
  
          Parameters
          ----------
          dataset : str
              The dataset containing the `table`.
          table : str
              The table to get the schema for
          project_id: str, optional
              The project of the dataset.
  
          Returns
          -------
          list
              A ``list`` of ``dict`` objects that represent the table schema. If
              the table doesn't exist, None is returned.