用tqdm包实现进度条：
tqdm基本用法：
from time import sleep
from tqdm import tqdm
for i in tqdm(range(10000)):
sleep(0.01)
tqdm更多用法：https://blog.csdn.net/langb2014/article/details/54798823
python3 不换行打印，多用于进度条 process bar
process = 0 # process bar
for i in user:
process += 1
print("\rProcess: %f " % (process/len(user)), end='')
process_code()
更多样式：
proc += 1
print('\r loading... %.2f %%' % (process/len(user)*100), end='')
python2:
对于py2来讲，主要起作用的是末尾的逗号：
print '\r loading... {:.3f}' .format( (float(proces))/len(user)*100 ) ,
print('%.3f' % 1.12345678) # Let's take 3 decimal places
print'{:.3f}'.format(3.14159)