def METHOD_NAME(a_dict):
    """Remove empty values from a multi level dictionary.
    :return a cleaned dictionary.
    """
    new_dict = {}
    for k, v in a_dict.items():
        if isinstance(v, dict):
            v = METHOD_NAME(v)
        elif isinstance(v, list):
            v = [el for el in v if el]
        if v:
            new_dict[k] = v
    return new_dict or None