@Contract(pure = true)
  @Override
  public @Nullable PsiElement extractElementFromSymbol(@NotNull Symbol symbol) {
    if (symbol instanceof Psi2Symbol) {
      return ((Psi2Symbol)symbol).getElement();
    }
    else {
      // If the Symbol is brand new,
      // then the client should implement proper Symbol-based APIs,
      // hence we consider brand-new Symbol implementations as inapplicable for old APIs
      return null;
    }
  }
@Contract(pure = true)
  @Override
  public @Nullable PsiElement extractElementFromSymbol(@NotNull Symbol symbol)