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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 _parse_incval(incunit, incval):
        ''' Parse a non-day increment value. Should be an integer or a comma-separated integer list. '''
        try:
            retn = [int(val) for val in incval.split(',')]
        except ValueError:
            return None

        return retn[0] if len(retn) == 1 else retn