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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 serialize(self, *args, **kwargs):
 """ Modified to allow additional labels to be passed in. """

        if 'labels' in kwargs:
            # populate labels from outside the local graph
            self._labels.update(kwargs['labels'])
        super(HtmlTurtleSerializer, self).serialize(*args, **kwargs)