def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def profile_iterable(self, iterable: Iterable, action_name: str) -> Generator:
        iterator = iter(iterable)
        while True:
            try:
                self.start(action_name)
                value = next(iterator)
                self.stop(action_name)
                yield value
            except StopIteration:
                self.stop(action_name)
                break