python - 如何在不导入的情况下将列表列表转换为单个列表

Question

我的 list 是:

a = [[1,2], [23,51,6], ["Hi", "hello"]]

我要输出:

a = [ 1,2,23 51,6, "Hi", "hello"]

Answer 1

使用 list comprehension :

>>> a = [[1,2], [23,51,6], ["Hi", "hello"]]
>>> [x for xs in a for x in xs]
[1, 2, 23, 51, 6, 'Hi', 'hello']