1、sorted
print(sorted([-5,3,-4,2,-1],key=abs)) # [-1,2,3,-4,-5]
list2 = ['sunv',(1,2),'a',[1,2,3]]
print(sorted(list2,key=len,reverse=True)) # ## ['sunv', [1, 2, 3], (1, 2), 'a']
2、max/min
print(max(dic,key=lambda k:dic[k]))3、函数的关键字参数(key=balabala)
print(min([-9,2,23,59],key = abs)) # 输出绝对值最小的数 # 2
4、