code: @Beta
      public static <A, T> Consumer<T> sc(final Object mutex, final A a, final BiConsumer<A, T> biConsumer) {
          N.checkArgNotNull(mutex, "mutex");
          N.checkArgNotNull(biConsumer, "biConsumer");
  
          return new Consumer<T>() {
              @Override
              public void accept(T t) {
                  synchronized (mutex) {
                      biConsumer.accept(a, t);
                  }
              }
          };
      }
docs: Synchronized {@code Consumer}
  
  @param mutex to synchronized on
  @param a
  @param biConsumer
  @return