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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def definition_package(cls):
 """Helper method for creating creating the package of a definition. Returns: Name of package that definition belongs to. """

        outer_definition = cls.message_definition()
        if not outer_definition:
            return util.get_package_for_module(cls.__module__)
        return outer_definition.definition_package()