def METHOD_NAME(self, infos: dict, list_info: list) -> List[dict]:
    """Process episode statistics.
    `RecordEpisodeStatistics` wrapper add extra
    information to the info. This information are in
    the form of a dict of dict. This method process these
    information and add them to the info.
    `RecordEpisodeStatistics` info contains the keys
    "r", "l", "t" which represents "cumulative reward",
    "episode length", "elapsed time since instantiation of wrapper".
    Args:
        infos (dict): infos coming from `RecordEpisodeStatistics`.
        list_info (list): info of the current vectorized environment.
    Returns:
        list_info (list): updated info.
    """
    episode_statistics = infos.pop("episode", False)
    if not episode_statistics:
        return list_info
    episode_statistics_mask = infos.pop("_episode")
    for i, has_info in enumerate(episode_statistics_mask):
        if has_info:
            list_info[i]["episode"] = {}
            list_info[i]["episode"]["r"] = episode_statistics["r"][i]
            list_info[i]["episode"]["l"] = episode_statistics["l"][i]
            list_info[i]["episode"]["t"] = episode_statistics["t"][i]
    return list_info