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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 _contiguous_slices(self):
 """Internal iterator over contiguous slices in RangeSet."""

        k = j = None
        for i in self._sorted():
            if k is None:
                k = j = i
            if i - j > 1:
                yield slice(k, j + 1, 1)
                k = i
            j = i
        if k is not None:
            yield slice(k, j + 1, 1)