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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 launch_app(self, app_id, force_launch=False, callback_function=False):
 """ Launches an app on the Chromecast. Will only launch if it is not currently running unless force_launch=True. """


        if not force_launch and self.app_id is None:
            self.update_status(lambda response:
                               self._send_launch_message(app_id, force_launch,
                                                         callback_function))
        else:
            self._send_launch_message(app_id, force_launch, callback_function)