code: function getDatabase(client, db, name, done) {
    if (typeof name === 'function') {
      done = name;
      name = db.databaseName;
    }
  
    const spec = {
      dbStats: 1
    };
  
    const options = {};
    debug('running dbStats for `%s`...', name);
    client.db(name).command(spec, options, function(err, res) {
      if (err) {
        debug('dbStats failed. Falling back to no stats.');
        res = {};
      } else {
        debug('got dbStats for `%s`', name, res);
      }
      res.db = res.db || name;
      done(null, parseDatabase(res));
    });
  }
docs: @param {MongoClient} client - The client.
  @param {DB} db - The db.
  @param {String} name - The name.
  @param {Function} done - The callback.
  
  @example
  {
  _id: 'yelp',
  name: 'yelp',
  document_count: 656617,
  storage_size: 200200192,
  index_count: 3,
  index_size: 5496832
  }