递归版flatten函数

[python]代码库

from collections.abc import *

def flatten(lst, out_lst=None):
    if out_lst is None:
        out_lst = []
    for i in lst:
        if isinstance(i, Iterable): # 判断i是否可迭代
            flatten(i, out_lst)  # 尾数递归
        else:
            out_lst.append(i)    # 产生结果
    return out_lst