code: public static CircuitBreakerCallAdapter of(final CircuitBreaker circuitBreaker, final Predicate<Response> successResponse) {
          return new CircuitBreakerCallAdapter(circuitBreaker, successResponse);
      }
docs: Create a circuit-breaking call adapter that decorates retrofit calls
  @param circuitBreaker circuit breaker to use
  @param successResponse {@link Predicate} that determines whether the {@link Call} {@link Response} should be considered successful
  @return a {@link CallAdapter.Factory} that can be passed into the {@link Retrofit.Builder}