public int CompareTo(Polinom<T> A) {
      return _polinomDictionary.Keys.Max().CompareTo(A._polinomDictionary.Keys.Max());
    }

    int IComparable.CompareTo(object obj) {
      if (!(obj is Polinom<T>)) {
        throw new ArgumentException("Это не полином", nameof(obj));
      }
      if (obj is null) {
        throw new ArgumentNullException("NULL", nameof(obj));
      }
      return CompareTo((Polinom<T>)obj);
    }