僅在Python中將這個列表，元組轉換成列表？

Question

我有一個這樣的名單：

[[(2L,)], [(3L,)]] 

我想轉換成到列表中，如：

[2, 3] 

我怎樣才能做到這一點？

Answer 1

使用列表理解：

如果元組只包含1項：

>>> lis = [[(2L,)], [(3L,)]] 
>>> [ y[0] for x in lis for y in x] 
[2L, 3L] 

如果元組包含超過1項：

>>> [z for x in lis for y in x for z in y] 
[2L, 3L] 

這將爲任何嵌套的工作量：

from collections import Iterable 
def flatten(collection): 
    for element in collection: 
    if isinstance(element, Iterable) and not isinstance(element, basestring): 
     for x in flatten(element): 
     yield x 
    else: 
     yield element 
>>> list(flatten(lis)) 
[2L, 3L] 
>>> lis = [[(2L,)], [(3L,(4,(5,)))]] 
>>> list(flatten(lis)) 
[2L, 3L, 4, 5] 

Answer 2

使用列表理解和長轉換爲int：

>>> L = [[(2L,)], [(3L,)]] 
>>> result = [int(y[0]) for x in L for y in x] 
>>> result 
[2, 3] 

Answer 3

爲了擺脫尾隨升，使用int()：

>>> L = [[(2L,)], [(3L,)]] 
>>> [int(i[0][0]) for i in L] 
[2, 3] 

Answer 4

>>> d = [[(2L,)], [(3L,)]] 
>>> map(lambda x: x[0][0], d) 
[2L, 3L]