Tuple2<T1, T2>.fromList  constructor 
      
      Tuple2<T1, T2>.fromList (
    
- List items
Create a new tuple value with the specified list items.
Implementation
factory Tuple2.fromList(List items) {
  if (items.length != 2) {
    throw ArgumentError('items must have length 2');
  }
  return Tuple2<T1, T2>(items[0] as T1, items[1] as T2);
}