private String parse(String line){
    StringBuilder res = new StringBuilder();
    for (int i=0; i<line.length(); i++){
      if(line.charAt(i) == '"'){
        res.append( opened ? "\'\'" : "``" );
        opened = !opened;
      }else{
        res.append(line.charAt(i));
      }
    }
    return res.toString();
  }