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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 load_to(self, last_level_load):
 """Set level where to load from."""

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