namespace System.Collections.ObjectModel
{
    [DebuggerDisplay("Count = {Count}")]
    [DebuggerTypeProxy(typeof(CollectionDebugView<?>))]
    [DefaultMember("Item")]
    public abstract class KeyedCollection<TKey, TItem> : Collection<TItem>
    {
        public bool TryGetValue(TKey key, out TItem item);
    }
}