做一个登陆循环

 1 or i in range(1,4):
 2 
 3     m=int(input('m:'))
 4 
 5     n=int(input('n:'))
 6 
 7     if m==123 and n==123:
 8 
 9         print('welcome'.title())
10 
11         break
12 
13     else:print('try again')
14 
15 else:print('goodbye')