code: public <T> T execute(final Callable<T> callable) throws Exception, ExhaustedRetryException {
          return execute(new RetryCallback<T, Exception>() {
              public T doWithRetry(RetryContext retryContext) throws Exception {
                  return callable.call();
              }
          });
      }
docs: *
  Execute a given {@link Callable} with retry logic.
  
  @param callable The callable to execute
  @param <T> The return type of the callable
  @return The result of the callable
  @throws Exception in the event that the callable throws
  @throws ExhaustedRetryException If all retry attempts have been exhausted