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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 _serialize_data(self, data):
 """Return serialized data or list of ids, depending on `hydrate_data` query param."""

        if self.request and self.request.query_params.get('hydrate_data', False):
            serializer = DataSerializer(data, many=True, read_only=True)
            serializer.bind('data', self)
            return serializer.data
        else:
            return [d.id for d in data]