def __GENERATED__(self, t, obj, ctx, /):
    used = 1
    try:
        x_countries = obj['countries']
    except KeyError:
        raise MissingFieldError(t, 'countries', ctx=ctx)
    else:
        v_countries = method_map[t_dict, type(x_countries), Context](self, dict1, x_countries, ctx)
    if used != len(obj):
        raise UnrecognizedFieldError(t, expected, obj.keys(), ctx=ctx)
    return World(v_countries)
