public void GetByIdElements_Success()
{
var dic = new SynchronizedDictionary<int, string, string>();
dic.Add(1, "Иванов", "value_1");
dic.Add(2, "Иванов", "value_2");
dic.Add(5, "Иванов", "value_3");
dic.Add(5, "Петров", "value_4");
var elementsById = dic.GetById(5);
Assert.AreEqual(2, elementsById.Count);
}