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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 transformFromNative(obj):
 """ Replace the datetime.timedelta in obj.value with an RFC2445 string. """

        if not obj.isNative:
            return obj
        obj.isNative = False
        obj.value = timedeltaToString(obj.value)
        return obj