docs: def record_prefix(required_type, factory):
      """
      Creates a record prefix for the specified record type.
  
      :param required_type: the type of the record using this prefix
      :param factory: field factory
      :return: the record prefix
      """
      field = record_type(required_type)
      field += factory.get_rule('transaction_sequence_n')
      field += factory.get_rule('record_sequence_n')
  
      # field.leaveWhitespace()
  
      return field