code: def to_query_parameters(parameters):
      
      if parameters is None:
          return []
  
      if isinstance(parameters, collections_abc.Mapping):
          return to_query_parameters_dict(parameters)
  
      return to_query_parameters_list(parameters)
docs: Converts DB-API parameter values into query parameters.
  
      :type parameters: Mapping[str, Any] or Sequence[Any]
      :param parameters: A dictionary or sequence of query parameter values.
  
      :rtype: List[google.cloud.bigquery.query._AbstractQueryParameter]
      :returns: A list of query parameters.