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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 start_tracker(self, id_, **kwargs):
 """ Starts a tracker for the time entry identified by `id_`. """

        data = None
        if kwargs:
            data = self._wrap_dict("tracker",
                self._wrap_dict("tracking_time_entry", kwargs))
        return self.patch("/tracker/{}.json".format(id_), data=data)