what does mongodb updateOne return code example

Example: updateone mongodb examples

const query = { "name": "football" };
const update = {
  "$push": {
    "reviews": {
      "username": "tombradyfan",
      "comment": "I love football!!!"
    }
  }
};
const options = { "upsert": false };

itemsCollection.updateOne(query, update, options)
  .then(result => {
    const { matchedCount, modifiedCount } = result;
    if(matchedCount && modifiedCount) {
      console.log(`Successfully added a new review.`)
    }
  })
  .catch(err => console.error(`Failed to add review: ${err}`))