for j in range(3):
    print('hello world')
for i in range(3):
    print('hello world',end='***')

hello world
hello world
hello world
hello world***hello world***hello world***

print('123','456','789')
print('123','456','789',sep='-')

123 456 789
123-456-789

import time
for i in range(10):
    time.sleep(1) #每秒打印一次
    print('#',end='',flush=True) #end需要指定为空，否则每一行打印一个#；flush需要指定为True，才会立刻打印