Method _push_exit_callback

Lib/contextlib.py:552–553

(self, callback, is_sync=True)

        self._push_exit_callback(_exit_wrapper, True)

    def _push_exit_callback(self, callback, is_sync=True):
        self._exit_callbacks.append((is_sync, callback))


# Inspired by discussions on http://bugs.python.org/issue13585