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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 reset_evaluators(self, evaluators):
 """Notify that some evaluators may be removed."""

        for obj_id, ev in self._tasks.copy().items():
            if ev not in evaluators:
                del self._tasks[obj_id]
                del self._objects[obj_id]
        ok = []
        for ev, obj_id in self._fetching:
            if ev in evaluators:
                ok.append((ev, obj_id))
        self._fetching = ok