apt-get install python3-pip # Python3
➜ ~ pip3 -V
pip 9.0.1 from /usr/lib/python3/dist-packages (python 3.6)
pip3 install flake8
执行目录的flake检测
python2.7 -m flake8 cinder # 2.7
python3.6 -m flake8 cinder # 3.6