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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 catch_and_return_token(func, self, *args, **kwargs):
 """Optionally defer exceptions and return a token instead When `__DEFER_STEP_ERRORS__` is set on the implementing class or instance, methods wrapped with this wrapper will catch and save their :python:`GSSError` exceptions and instead return the result token attached to the exception. The exception can be later retrived through :python:`_last_err` (and :python:`_last_tb` when Python 2 is in use). """


    try:
        return func(self, *args, **kwargs)
    except GSSError as e:
        if e.token is not None and self.__DEFER_STEP_ERRORS__:
            self._last_err = e
            # skip the "return func" line above in the traceback
            if six.PY2:
                self._last_tb = sys.exc_info()[2].tb_next.tb_next
            else:
                self._last_err.__traceback__ = e.__traceback__.tb_next

            return e.token
        else:
            raise