docs: public ExceptionSet duplicate() {
          ExceptionSet dup = factory.createExceptionSet();
          dup.exceptionSet.clear();
          dup.exceptionSet.or(this.exceptionSet);
          dup.explicitSet.clear();
          dup.explicitSet.or(this.explicitSet);
          dup.size = this.size;
          dup.universalHandler = this.universalHandler;
          dup.commonSupertype = this.commonSupertype;
  
          return dup;
      }