code: public CompletionStage<Map<String, Result<R>>> callSync(final SaltClient client, Target<?> target,
              AuthMethod auth) {
          return callSyncHelperNonBlock(client, target, auth, Optional.empty())
                  .thenApply(r -> r.get(0));
      }
docs: Calls a execution module function on the given target and synchronously
  waits for the result. Authentication is done with the token therefore you
  have to login prior to using this function.
  
  @param client SaltClient instance
  @param target the target for the function
  @param auth authentication credentials to use
  @return a map containing the results with the minion name as key