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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(self):
 """Start operating the strategy. Subclasses that override start() should call the super method before it does anything that uses the ioloop. This will attach to the sensor as an observer if :attr:`OBSERVE_UPDATES` is True, and sets :attr:`_ioloop_thread_id` using `thread.get_ident()`. """

        def first_run():
            self._ioloop_thread_id = get_thread_ident()
            if self.OBSERVE_UPDATES:
                self.attach()
        self.ioloop.add_callback(first_run)