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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 module_del(self, key):
 """ Deregister from python module change events. """

        if key in self._module_event_map:
            del self._module_event_map[key]
        if key in self._watch_modules.names:
            self._watch_modules.remove(key)