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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 patch(self, patch):
 """Change a bunch of node stats at once. This works similarly to ``update``, but only accepts a dict-like argument, and it recurses one level. The patch is sent to the LiSE core all at once, so this is faster than using ``update``, too. :param patch: a dictionary. Keys are node names, values are other dicts describing updates to the nodes, where a value of None means delete the stat. Other values overwrite. """

        self.engine.handle(
            'update_nodes',
            char=self.character.name,
            patch=patch,
            block=False
        )
        for node, stats in patch.items():
            nodeproxycache = self[node]._cache
            for k, v in stats.items():
                if v is None:
                    del nodeproxycache[k]
                else:
                    nodeproxycache[k] = v