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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 now(self, when=None):
 """Set the current value to the correct tuple based on the seconds since the epoch. If 'when' is not provided, get the current time from the task manager. """

        if when is None:
            when = _TaskManager().get_time()
        tup = time.localtime(when)

        self.value = (tup[0]-1900, tup[1], tup[2], tup[6] + 1)

        return self