def get_nested_value(data_dict, key_list):
    """Retrieving values in a nested iterable with a key list"""
    return reduce(lambda dictionary, key: dictionary[key], key_list, data_dict)


def set_nested_value(data_dict, key_list, value):
    """Setting values in a nested iterable with a key list"""
    get_nested_value(data_dict, key_list[:-1])[key_list[-1]] = value