num = 123
print('{:<08d}'.format(num))
print('{:>08d}'.format(num))
string = '123'
print(string.ljust(8, '0'))
print(string.rjust(8, '0'))
print(string[::-1].zfill(8)[::-1])

12300000
00000123
12300000
00000123
12300000

该分类下的相关小册推荐：