let ratingArr = [];

      const moviesByNolan = watchList.filter(watchList => watchList['Director'] === 'Christopher Nolan' ? ratingArr.push(Number(watchList['imdbRating'])) : false);


    console.log(ratingArr);


    const reducer = (accumulator, currentValue) => accumulator + currentValue;

    console.log(ratingArr.reduce(reducer));

    var averageRating = ratingArr.reduce(reducer) / ratingArr.length;