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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 timeFlip(self):
        '''
        Reverse the flow of time for this instance.

        Parameters
        ----------
        none

        Returns
        -------
        none
        '''
        for name in self.time_vary:
            exec('self.' + name + '.reverse()')
        self.time_flow = not self.time_flow