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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_task(self, func):
 """Start up a task"""

        task = self.loop.create_task(func(self))
        self._started_tasks.append(task)

        def done_callback(done_task):
            self._started_tasks.remove(done_task)

        task.add_done_callback(done_callback)
        return task