@Override
  public @Nullable PsiElement getKey() {
    PsiElement colon = findChildByType(YAMLTokenTypes.COLON);
    if (colon == null) {
      return null;
    }
    ASTNode node = colon.getNode();
    do {
      node = node.getTreePrev();
    } while(YAMLElementTypes.BLANK_ELEMENTS.contains(PsiUtilCore.getElementType(node)));

    if (node == null || PsiUtilCore.getElementType(node) == YAMLTokenTypes.QUESTION) {
      return null;
    }
    else {
      return node.getPsi();
    }
  }
@Override
  public @Nullable PsiElement getKey()