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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 EXPIRING_TOKEN_LIFESPAN(self):
 """ Return the allowed lifespan of a token as a TimeDelta object. Defaults to 30 days. """

        try:
            val = settings.EXPIRING_TOKEN_LIFESPAN
        except AttributeError:
            val = timedelta(days=30)

        return val