code: public static Marker createProvided(Provided provided) {
          requireNonNull(provided);
          return new Marker(Marker.class.getResource("/markers/" + provided.getFilename()), provided.getOffsetX(),
                  provided.getOffsetY());
      }
docs: return a provided Marker with the given color.
  
  @param provided
  desired color
  @return Marker
  @throws NullPointerException
  when provided is null