code: function(items, iterator, done) {
      done = done || function() {};
      var results = [];
      var failure = false;
      var expected = items.length;
      var current = -1;
  
      function callback(err, result) {
        if (err) return done(err);
  
        results.push(result);
  
        if (current == expected) {
          return done(null, results);
        } else {
          next();
        }
      }
  
      function next() {
        current += 1;
  
        var item = items[current];
        iterator(item, callback);
      }
  
      next()
    }
docs: Works like async.eachSeries