private void checkAsyncKeyword(@NotNull PsiElement node) {
    final ASTNode asyncNode = node.getNode().findChildByType(PyTokenTypes.ASYNC_KEYWORD);
    if (asyncNode != null) {
      registerForAllMatchingVersions(level -> level.isOlderThan(LanguageLevel.PYTHON35) && registerForLanguageLevel(level),
                                     PyPsiBundle.message("INSP.compatibility.feature.support.this.syntax"),
                                     node,
                                     asyncNode.getTextRange(),
                                     true);
    }
  }
private void checkAsyncKeyword(@NotNull PsiElement node)