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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 transformChildrenToNative(self):
 """ Recursively replace children with their native representation. Sort to get dependency order right, like vtimezone before vevent. """

        for childArray in (self.contents[k] for k in self.sortChildKeys()):
            for child in childArray:
                child = child.transformToNative()
                child.transformChildrenToNative()