def _serialize(self):
result = { a: getattr(self, a) for a in type(self).properties<EOL>if type(self).properties[a].mutable }<EOL>for k, v in result.items():<EOL><INDENT>if isinstance(v, Base):<EOL><INDENT>result[k] = v.id<EOL><DEDENT><DEDENT>return result<EOL>
A helper method to build a dict of all mutable Properties of
this object