Python 2

Мне нравится следующее:

print 'Downloading File FooFile.txt [%d%%]\r'%i,

Демо:

import time

for i in range(100):
    time.sleep(0.1)
    print 'Downloading File FooFile.txt [%d%%]\r'%i,

Python 3

print('Downloading File FooFile.txt [%d%%]\r'%i, end="")

Демо:

import time

for i in range(100):
    time.sleep(0.1)
    print('Downloading File FooFile.txt [%d%%]\r'%i, end="")

Консоль отладчика PyCharm с Python 3

# On PyCharm Debugger console, \r needs to come before the text.
# Otherwise, the text may not appear at all, or appear inconsistently.
# tested on PyCharm 2019.3, Python 3.6

import time

print('Start.')
for i in range(100):
    time.sleep(0.02)
    print('\rDownloading File FooFile.txt [%d%%]'%i, end="")
print('\nDone.')

py