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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 transformToNative(obj):
 """ Convert comma separated periods into tuples. """

        if obj.isNative:
            return obj
        obj.isNative = True
        if obj.value == '':
            obj.value = []
            return obj
        tzinfo = getTzid(getattr(obj, 'tzid_param', None))
        obj.value = [stringToPeriod(x, tzinfo) for x in obj.value.split(",")]
        return obj