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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 run_activity(self):
 """ runs the method that referenced from current task """

        activity = self.current.activity
        if activity:
            if activity not in self.wf_activities:
                self._load_activity(activity)
            self.current.log.debug(
                "Calling Activity %s from %s" % (activity, self.wf_activities[activity]))
            self.wf_activities[self.current.activity](self.current)