text: function houseParty(args) {
      let quests = [];
      for (let line of args) {
          let tokens = line.split(' ');
          let questName = tokens[0];
  
          if (tokens.length === 3) {
              if (quests.includes(questName)) {
                  console.log(`${questName} is already in the list!`);
              } else {
                  quests.push(questName);
              }
          } else if (tokens.length === 4) {
              let indexOfQuest = quests.indexOf(questName);
              if (indexOfQuest < 0) {
                  console.log(`${questName} is not in the list!`);
              } else {
                  quests.splice(indexOfQuest, 1);
              }
          }
      }
  
      quests.forEach(q => console.log(q));
  }
  
  houseParty([
      'Allie is going!',
      'George is going!',
      'John is not going!',
      'George is not going!'
  ]);