def get_item_list(source: dict, key: str) -> list:
    """Retrieves a list from a dictionary even if the key is not present.

    Args:
        source (dict): The dictionary to search through
        key (str): The lookup key, noting it does not have to exist in the dict

    Returns:
        list: The corresponding list for the given key or an empty list if not present
    """
    items = source.get(key)
    items = items if isinstance(items, list) else []
    return items