python虚拟环境

sudo easy_install virtualenv

或者是：

sudo pip3 install virtualenv

ubantu安装
sudo apt-get install python-virtualenv

创建虚拟环境
$ cd /home/shiyanlou/Code
$ mkdir myproject && cd myproject
$ virtualenv -p /usr/bin/python3 venv
New python executable in venv/bin/python
Installing distribute............done.

启动
. venv/bin/activate

windows下
venvscriptsactivate

全局安装 flask
sudo apt-get update
sudo pip3 install flask==1.0.2

体验最新的 flask
sudo pip3 install -U https://github.com/pallets/flask/archive/master.tar.gz