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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 add_labels(self, *args):
 """Add labels to this issue. :param str args: (required), names of the labels you wish to add :returns: list of :class:`Label`\ s """

        url = self._build_url('labels', base_url=self._api)
        json = self._json(self._post(url, data=args), 200)
        return [Label(l, self) for l in json] if json else []