Why does async await return undefined as a result of a database query?

Question

JavaScript

Below is a function that would have to find a user in the database and return it.
If I understand correctly, then MongoClient.connect returns null, but if I returned the user in the callback, can I get it in the resp variable ?
In turn, in function log returns null or the user to me, and resp returns undefined.
Am I doing something wrong with async/await, or should I return the user otherwise?
Essentially, I have to check the login and pass in this function, but it must return something.
Please tell me how to verify the login and pass.

async function checkIfUserExists(user) {
  const resp = await MongoClient.connect(mongoUrl,
    {
      useNewUrlParser: true,
      useUnifiedTopology: true
    },
    async function(err, db) {
      if (err) throw err;

      let dbo = await db.db("todo");

      let user = await dbo.collection("users").findOne(user);

      console.log('in function log');
      console.log(user);

      return user;
  });

  console.log('resp');
  console.log(resp);

  return resp;
}

Answer 1

Shaw is some kind of crap, there is a callback for the connection if there are no promises. I haven't looked at their lib for a long time, but it returns a promise if there is no callback everywhere, as far as I remember.

const db = await MongoClient.connect(mongoUrl)
let dbo = await db.db("todo");
 let user = await dbo.collection("users").findOne(user);
console.log(user);