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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_offsets(self, offsets):
 """ Sorts the input list of integer offsets, ensures that values are contiguous. """

        offsets.sort()
        for i in range(len(offsets) - 1):
            assert offsets[i] + 1 == offsets[i + 1], \
                "Offsets not contiguous: %s" % (offsets,)
        return offsets