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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 shift(self, h=0, m=0, s=0, ms=0, frames=None, fps=None):
 """ Shift start and end times. See :meth:`SSAFile.shift()` for full description. """

        delta = make_time(h=h, m=m, s=s, ms=ms, frames=frames, fps=fps)
        self.start += delta
        self.end += delta