code: public DepictionGenerator withAtomMapHighlight(Color[] colors) {
          DepictionGenerator copy = new DepictionGenerator(this);
          copy.highlightAtomMap = true;
          copy.atomMapColors = Arrays.copyOf(colors, colors.length);
          return copy;
  
      }
docs: Adds to the highlight the coloring of reaction atom-maps. The
  optional color array is used as the pallet with which to
  highlight. If none is provided a set of high-contrast colors
  will be used.
  
  @param colors array of colors
  @return new generator for method chaining
  @see #withAtomMapNumbers()
  @see #withAtomMapHighlight()