docs: def lookup_int(values, name=None):
      """
      Lookup field which transforms the result into an integer.
  
      :param values: values allowed
      :param name: name for the field
      :return: grammar for the lookup field
      """
      field = basic.lookup(values, name)
  
      field.addParseAction(lambda l: int(l[0]))
  
      return field