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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 remove_key(self, key):
 """Remove own key, value"""

        try:
            self._own_keys.discard(key)
            if self._parent and self._parent.has_key(key):
                self._container[key] = self._parent[key]
            else:
                del self._container[key]
        except KeyError:
            pass