关于sys.stdout和print的区别详解

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.

f = open('test.txt','a')
print('this is a test',file=f)

# -*- coding: utf-8 -*-
from tqdm import tqdm
import time
import sys
 
for i in tqdm(range(100)):
 time.sleep(.1)
for i in range(100):
 a = (i+1)/5
 b = 20-a
 #sys.stdout.write('\rconvert image %d/%d'%(i,b))
 
 sys.stdout.write('\r|%s%s|%d%%'%(a*'▇',b*' ',i+1))
 sys.stdout.flush()
 time.sleep(.1)

from tqdm import tqdm 
import time
for i in tqdm(range(10000)): 
 time.sleep(0.01)