code: public Object get(Object key) {
          Object val = super.get(key);
          if (val == null && key instanceof Option) {
              val = ((Option)key).defaultValue;
          }
  
          return val;
      }
docs: Looks up key in the options.
  
  If key is an Option, its default value will be returned if the key
  isn't found.
  
  @param key
  @return