sortedBy method
Returns a sorted iterable based on a computed key.
Set desc to true for descending order.
Implementation
Iterable<T> sortedBy(Comparable Function(T e) key, {bool desc = false}) {
final list =
toList()..sort((a, b) => key(a).compareTo(key(b)) * (desc ? -1 : 1));
return list;
}