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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 _exit_door(self, _input):
 """This function is passed to each SelectableObject as a callback The SelectableObjects have to call it once there are ready"""

        self.results.append(_input)
        if self._ended:
            return
        self._ended = True
        self._release_all()