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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 _get_type_list(self, props):
 """Return a list of non-primitive types used by this object."""

        type_list = []
        for k, v in list(props.items()):
            t = self._get_property_type(v)
            if t is not None:
                type_list.append(t)
        return sorted(type_list)