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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 get_offset(cls, info):
 """Calculate the offset to the Xing header from the start of the MPEG header including sync based on the MPEG header's content. """


        assert info.layer == 3

        if info.version == 1:
            if info.mode != 3:
                return 36
            else:
                return 21
        else:
            if info.mode != 3:
                return 21
            else:
                return 13