@Nullable
  public PyType getElementType(int index) {
    if (isHomogeneous()) {
      return getIteratedItemType();
    }
    List<PyType> elementTypes = myUnpackedTupleType.getElementTypes();
    return index >= 0 && index < elementTypes.size() ? elementTypes.get(index) : null;
  }
@Nullable
  public PyType getElementType(int index)