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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 del_key(self, k):
 """Delete the key and any configuration for it"""

        if k not in self.mirror:
            raise KeyError
        del self.proxy[k]
        if '_config' in self.proxy and k in self.proxy['_config']:
            del self.proxy['_config'][k]