python：print和format

查询帮助：
help(print)
Help on built-in function print in module builtins:

print(...)
print(value, ..., sep=' ', end='\n', file=sys.stdout, flush=False)  

Prints the values to a stream, or to sys.stdout by default.
Optional keyword arguments:
file:  a file-like object (stream); defaults to the current sys.stdout.
sep:   string inserted between values, default a space.
end:   string appended after the last value, default a newline.
flush: whether to forcibly flush the stream

print 打印多值以逗号分隔，分隔符默认是空格（sep=‘ ’），新行符是‘\n’

print(5,6,sep='>>')
	5>>6

print(5,6,sep='>>',end='---')
print(8)
	5>>6---8

{}代表format中的值，{0}代表第一个

print(' {}	{}aa{}'.format(1,2,3)) 
	1	2aa3


print(' {2}	{2}aa{2}'.format(1,2,3))
    3	3aa3