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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_items(self, serializer, kind, items):
 """Return serialized items or list of ids, depending on `hydrate_XXX` query param."""

        if self.request and self.request.query_params.get('hydrate_{}'.format(kind), False):
            serializer = serializer(items, many=True, read_only=True)
            serializer.bind(kind, self)
            return serializer.data
        else:
            return [item.id for item in items]