def list_sum(num_list):
    if len(num_list) == 1:
        return num_list[0]
    else:
        return num_list[0] + list_sum(num_list[1:])


print(list_sum([1]))
print(list_sum([1, 3, 5, 7, 9, 11]))
print(list_sum([1, 7, 11, 21, 211]))
