def operation_helper(
        self, path=None, operations=None, methods=None, func=None, **kwargs
    ):
        """May mutate operations.
        :param str path: Path to the resource
        :param dict operations: A `dict` mapping HTTP methods to operation object. See
        :param list methods: A list of methods registered for this path
        """
        for method in methods:
            yaml_doc_string = yaml_utils.load_operations_from_docstring(func.__doc__)
            yaml_doc_string = yaml.safe_load(
                str(yaml_doc_string).replace(
                    "{{self.__class__.__name__}}", self.__class__.__name__
                )
            )
            if yaml_doc_string:
                operations[method.lower()] = yaml_doc_string.get(method.lower(), {})
            else:
                operations[method.lower()] = {}