python 圣诞树、九九乘法表

#圣诞树：
*for i in range(7,9):
    for k in range(1,i+1):
        print(format('*'*k,'>12') +format('*'*(k-1),'<12'))
for j in range(1,5):
    print(format("*"*3,'^24'))

#九九乘法表：
k = 1
sum = 1
while k < 10:
    for num in range(1,k+1):
        sum=k * num
        print(str(k) + '*' + str(num) +'=' + str(sum),end=' ')
    print('')
    k +=1