python基礎教程中（第2版 修訂版）p155頁有這樣一段程式碼：

def flatten(nested):
    try:
        for sublist in nested:
            for element in flatten(sublist):
                yield element
    except TypeError:
        yield nested
list(flatten([[[1], 2], 3, 4, [5, [6, 7]], 8]))

輸出：
[1, 2, 3, 4, 5, 6, 7, 8]

　　這是遞迴生成器的使用。其它遞迴生成器可參考 

　　除錯程式碼：

def flatten(nested):
    try:
        print(nested)
        for sublist in nested:
            print('\n')
            print(sublist)
            for element in flatten(sublist):
                print(element)
                yield element
    except TypeError:
        
 
yield nested
list(flatten([[[1], 2], 3, 4, [5, [6, 7]], 8]))

輸出：
[[[1], 2], 3, 4, [5, [6, 7]], 8]


[[1], 2]
[[1], 2]


[1]
[1]


1
1
1
1
1


2
2
2
2


3
3
3


4
4
4


[5, [6, 7]]
[5, [6, 7]]


5
5
5
5


[6, 7]
[6, 7]


6
6
6
6
6


7
7
7
7
7


8
8
8
[1, 2, 3, 4, 5, 6, 7, 8]

　　可見，其中的yield nested用於生成每個最終的輸出值，而其中yield element的作用是向上傳遞yield nested的值，相當於接力器，所以每個值print(element)輸出的數量不一樣，越多說明遞迴呼叫的越深，需要傳遞的層數越多。