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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 get_proc_return_status(self):
 """ Last stored proc result """

        if self._session is None:
            return None
        if not self._session.has_status:
            self._session.find_return_status()
        return self._session.ret_status if self._session.has_status else None