public void ExceptAllWithTest2()
{
var bag = new HashBag <int> {
3, 5, 1, 4, 6, 2, 3, 5, 1, 4, 6, 2
};
var l = new List <int> {
1, 3, 5
};
bag.ExceptAllWith(l);
Assert.Equal(new[] { 4, 4, 6, 6, 2, 2 }, bag);
}