@Override public String toString(){
  StringBuilder buf=new StringBuilder();
  int i=0;
  for (  PseudoOp op : contents) {
    buf.append(String.format("%4d : %s%n",i++,op));
  }
  return buf.toString();
}

@ Override public String toString ( ) { StringBuilder buf = new StringBuilder ( ) ; int i = 0 ; for ( PseudoOp op : contents ) { buf . append ( String . format ( "%4d : %s%n" , i ++ , op ) ) ; } return buf . toString ( ) ; }
format the p - code for this method
