In your run_thread() method, the line:
t1 = threading.Thread(target=self.process_some_data())
runs the process_some_data() method, then sets the target of the created thread to the return of that method. I think you just need to remove the () from that method, so that the target is set to the process_some_data method and not its return:
t1 = threading.Thread(target=self.process_some_data)
CLICK HERE to find out more related problems solutions.