def __parameter_default(self, final_subfield):
if final_subfield.default:<EOL><INDENT>if isinstance(final_subfield, messages.EnumField):<EOL><INDENT>return final_subfield.default.name<EOL><DEDENT>else:<EOL><INDENT>return final_subfield.default<EOL><DEDENT><DEDENT>
Returns default value of final subfield if it has one.

        If this subfield comes from a field list returned from __field_to_subfields,
        none of the fields in the subfield list can have a default except the final
        one since they all must be message fields.

        Args:
          final_subfield: A simple field from the end of a subfield list.

        Returns:
          The default value of the subfield, if any exists, with the exception of an
              enum field, which will have its value cast to a string.