code: def _format_operation_dict(operation, parameters):
      
      formatted_params = {}
      for name in parameters:
          escaped_name = name.replace("`", r"\`")
          formatted_params[name] = "@`{}`".format(escaped_name)
  
      try:
          return operation % formatted_params
      except KeyError as exc:
          raise exceptions.ProgrammingError(exc)
docs: Formats parameters in operation in the way BigQuery expects.
  
      The input operation will be a query like ``SELECT %(namedparam)s`` and
      the output will be a query like ``SELECT @namedparam``.
  
      :type operation: str
      :param operation: A Google BigQuery query string.
  
      :type parameters: Mapping[str, Any]
      :param parameters: Dictionary of parameter values.
  
      :rtype: str
      :returns: A formatted query string.
      :raises: :class:`~google.cloud.bigquery.dbapi.ProgrammingError`
          if a parameter used in the operation is not found in the
          ``parameters`` argument.