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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 store_from(self, last_level_store):
 """Set level where to store to."""

        assert isinstance(last_level_store, Cache), \
            "last_level needs to be a Cache object."
        assert last_level_store.store_to is None, \
            "last_level_store must be a last level cache (.store_to is None)."
        self.last_level_store = last_level_store