请问如何用一行代码代替，谢谢！
for i in [[0, '2'], [4, '9'], [50, '63'], [445, '63']]:
if i[0] == 50:
a = i[1]
b = i[4]
break
可以使用列表推导式来代替循环：
a, b = next((i[1], i[4]) for i in [[0, '2'], [4, '9'], [50, '63'], [445, '63']] if i[0] == 50)