python 打印不重复的三位数字

#1,2,3,4组成不重复的三位数字
sum=0
for i in range(1,5):
    for j in  range(1,5):
        for k in range(1,5):
            if (i==j)or(j==k)or(i==k):
                continue

            print("三位数字分别是：",i,j,k)
            sum = sum + 1

print("一共有",sum,"个三位数字")