docs: public static MutableInt fromExternal(final IntSupplier s, final IntConsumer c) {
          return new MutableInt() {
              @Override
              public int getAsInt() {
                  return s.getAsInt();
              }
  
              @Override
              public Integer get() {
                  return getAsInt();
              }
  
              @Override
              public MutableInt set(final int value) {
                  c.accept(value);
                  return this;
              }
          };
      }