@Override
  protected @Nullable PsiElement addDeclaration(@NotNull PsiElement expression,
                                                @NotNull PsiElement declaration,
                                                @NotNull IntroduceOperation operation) {
    return doIntroduceParameter(expression, (PyAssignmentStatement)declaration);
  }
@Override
  protected @Nullable PsiElement addDeclaration(@NotNull PsiElement expression,
                                                @NotNull PsiElement declaration,
                                                @NotNull IntroduceOperation operation)