for循环
a = [1,2,3,4,5,6] b = [] for i in a: b.append(str(i))
列表生成式：
c = [ str(i) for i in a]
列表生成式还可以写的稍微复杂一些，比如可以加个if判断
d = [ str(i) for i in a if i%2!=0 ]
