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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 async_run(self, keyword, *args, **kwargs):
        ''' Executes the provided Robot Framework keyword in a separate thread and immediately returns a handle to be used with async_get '''
        handle = self._last_thread_handle
        thread = self._threaded(keyword, *args, **kwargs)
        thread.start()
        self._thread_pool[handle] = thread
        self._last_thread_handle += 1
        return handle