code: public SELF size(int min, int max) {
  
      return size(new Range<>(Integer.valueOf(min), Integer.valueOf(max)));
    }
docs: @see #size(Range)
  
  @param min the minimum {@link Map#size() size} allowed.
  @param max the maximum {@link Map#size() size} allowed.
  @return this build instance for fluent API calls.