static <T> T executeCallable(Observation observation, Callable<T> callable) throws Exception {
        return decorateCallable(observation, callable).call();
    }
@Test
    public void shouldExecuteCallable() throws Throwable {
        given(helloWorldService.returnHelloWorldWithException()).willReturn("Hello world");

        String value = Observations
            .executeCallable(observation, helloWorldService::returnHelloWorldWithException);

        assertThatObservationWasStartedAndFinishedWithoutErrors();
        assertThat(value).isEqualTo("Hello world");
        then(helloWorldService).should(times(1)).returnHelloWorldWithException();
    }