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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):
 """ Turn obj.value into a date or datetime. """

        if obj.isNative:
            return obj
        obj.isNative = True
        if obj.value == '':
            return obj
        obj.value=obj.value
        obj.value=parseDtstart(obj, allowSignatureMismatch=True)
        if getattr(obj, 'value_param', 'DATE-TIME').upper() == 'DATE-TIME':
            if hasattr(obj, 'tzid_param'):
                # Keep a copy of the original TZID around
                obj.params['X-VOBJ-ORIGINAL-TZID'] = [obj.tzid_param]
                del obj.tzid_param
        return obj