text: exports.changeLanguage = function(req,res){
      let lang1 = req.body.txt_language; //sent by a form
      let lang2 = req.params.lang; //sent in the URL
  
      req.session.lang = lang2;
  
      res.redirect('../index.html');
  }
  
  exports.getLanguage = function(req,res){
      res.status(200);
      res.send(req.session.lang);
      res.end();
  }