text: function mutateMyStrings(stringOne, stringTwo){
  
    let splitOne = stringOne.split('');
    let splitTwo = stringTwo.split('');
    let mutateMyString = stringOne.concat('\n');
     
     for (let i = 0; i < splitOne.length; i++) {
      if (splitOne[i] !== splitTwo[i]){
       splitOne[i] = splitTwo[i];
        mutateMyString = mutateMyString.concat(`${splitOne.join('')}\n`);
         }
  }
      return mutateMyString;
   
  
  }