def METHOD_NAME(self) -> Dict[str, Any]:
    """A master response to get_GetExperiment for a long-running experiment.
    This function models an experiment that may take a long time to complete. The first
    two times get_experiment is called, the experiment state is still in a
    bindings.experimentv1State.RUNNING. On the third call, its state is
    bindings.experimentv1State.COMPLETED.
    Returns:
        If successful, a JSON-encoded sample experiment. Else None.
    """
    key = "get_experiment_longrunning_n_calls"
    n_calls = 2
    sample_experiment = sample_get_experiment()
    with lock:
        state[key] = state.get(key, 0) + 1
        if state[key] <= n_calls:
            sample_experiment.experiment.state = bindings.experimentv1State.RUNNING
        else:
            sample_experiment.experiment.state = bindings.experimentv1State.COMPLETED
    return sample_experiment.to_json()