def _yaml_add_comment(self, comment, key=NoComment, value=NoComment):
        # type: (Any, Optional[Any], Optional[Any]) -> None
        """values is set to key to indicate a value attachment of comment"""
        if key is not NoComment:
            self.yaml_key_comment_extend(key, comment)
            return
        if value is not NoComment:
            self.yaml_value_comment_extend(value, comment)
        else:
            self.ca.comment = comment
values is set to key to indicate a value attachment of comment
dynaconf/vendor/ruamel/yaml/comments.py