code: def _check_format(file_path, content):
      
      # TODO: replace with JSON schema validation
      if not content:
          # testcase file content is empty
          err_msg = u"Testcase file content is empty: {}".format(file_path)
          logger.log_error(err_msg)
          raise exceptions.FileFormatError(err_msg)
  
      elif not isinstance(content, (list, dict)):
          # testcase file content does not match testcase format
          err_msg = u"Testcase file content format invalid: {}".format(file_path)
          logger.log_error(err_msg)
          raise exceptions.FileFormatError(err_msg)
docs: check testcase format if valid