private static boolean isBooleanLiteral(@Nullable PsiElement element) {
    if (element instanceof PyBoolLiteralExpression) {
      return true;
    }
    return element instanceof PyReferenceExpression && (PyNames.TRUE.equals(element.getText()) || PyNames.FALSE.equals(element.getText()));
  }
private static boolean isBooleanLiteral(@Nullable PsiElement element)