python - 每次运行函数时，打印出列表的n个元素

Question

我有一个字符串列表，我需要创建一个函数，该函数每次运行时都会打印出列表的n个元素。
例如:

book1 = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o']

如果是n = 5，我第一次运行该函数的预期输出是:

a
b
c
d
e

第二次:

f
g
h
i
j

我尝试了这个:

def print_book(book):
    printed = book
    while printed != []:
        for i in range(0, len(book), 5):
            new_list = (book[i:i+5])
            for el in new_list:
                print(el)
        break
    del(printed[i:i+10])

然后，我要么打印出整个列表，要么每次运行该函数时都打印出前n个元素。
如果已经问过这个问题，请向我指出，我真的很感激。谢谢!

Answer 1

我猜你可以尝试以下应用于迭代器book的用户功能

def print_book(book):
    cnt = 0
    while cnt < 5:
        try:
            print(next(book))
        except StopIteration:
            print("You have reached the end!")
            break
        cnt += 1

这样

>>> bk1 = iter(book1)
>>> print_book(bk1)
a
b
c
d
e
>>> print_book(bk1)
f
g
h
i
j
>>> print_book(bk1)
k
l
m
n
o
>>> print_book(bk1)
You have reached the end!