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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_frozen(self):
 """ Removes _frozen attribute from this instance and all its child configurations. """

        self.__delattr__('_frozen')
        for attr, val in self.__dict__.items():
            if isinstance(val, Config) and hasattr(val, '_frozen'):
                val.__del_frozen()