from collections import abc


def get_from_nested(dic, keys=None, default=None):
    """
    >>> get_from_nested({'hoge': {'fuga': 1}}, keys=['hoge'], default=[])
    {'fuga': 1}
    >>> get_from_nested({'hoge': {'fuga': 1}}, keys=['hoge', 'fuga'], default=[])
    1
    >>> get_from_nested({'hoge': {'fuga': 1}}, keys=['hoge', 'fuga', 'yeah'], default=[])
    []
    >>> get_from_nested({}, keys=['hoge', 'fuga', 'yeah'], default=[])
    []
    >>> get_from_nested({'hoge': {'fuga': 1}}, keys=[])
    >>> get_from_nested({'hoge': {'fuga': 1}})
    """
    keys = keys or []
    if keys:
        head, *tail = list(keys)
        value = dic.get(head, default)
        if isinstance(value, abc.Mapping) and tail:
            return get_from_nested(value, tail, default=default)
        elif tail:
            # キーは続いてるけどすでに値が見つかってる
            return default
        else:
            return value
    else:
        return default

if __name__=='__main__':
    import doctest
    doctest.testmod()