[flake8](http://flake8.pycqa.org) testing of https://github.com/CriseLYJ/awesome-python-login-model on Python 3.7.1
$ __flake8 . --count --select=E9,F63,F72,F82 --show-source --statistics__
```
./guoke/guoke_spider.py:76:41: F821 undefined name 'file_path'
print('Already Downloaded', file_path)
^
./facebook/facebook.py:52:27: E999 SyntaxError: invalid syntax
print '{0}:{1}:{2}'.format(fb_dtsg, user_id, xs)
^
./baidu2/baidu.py:193:13: F821 undefined name 'raw_input'
input = raw_input
^
1 E999 SyntaxError: invalid syntax
2 F821 undefined name 'raw_input'
3
```
__E901,E999,F821,F822,F823__ are the "_showstopper_" [flake8](http://flake8.pycqa.org) issues that can halt the runtime with a SyntaxError, NameError, etc. These 5 are different from most other flake8 issues which are merely "style violations" -- useful for readability but they do not effect runtime safety.
* F821: undefined name `name`
* F822: undefined name `name` in `__all__`
* F823: local variable name referenced before assignment
* E901: SyntaxError or IndentationError
* E999: SyntaxError -- failed to compile a file into an Abstract Syntax Tree