Derive Collection class:Override Add,Insert,Remove methods

These methods are not overridable,
will be more correctly to override InsertItem,RemoveItem methods, they will be called from other methods Add,Insert,Remove , etc

using System.Collections.ObjectModel;
using System.Diagnostics;
using System;
namespace CollectionTest
{
    class Program
    {
        static void Main(string[] args)
        {
            Debug.Write("MAIN");
            LimitedCollection<String> col = new LimitedCollection<String>();
            col.Add("hello");
            col.Insert(0,"hello");

        }
    }
    public class LimitedCollection<T> : Collection<T>
    {
        protected override void InsertItem(int index, T item)
        {
            base.InsertItem(index, item);
            Debug.Write("InsertItem called");
        }
    }
}

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