1、使用场景： 1.web微服务

2、python2.7安装 sudo pip install --upgrade pip 10.0.1 -> 18.1 pip --version = 18.1 pip install tornado

验证
error: Cannot uninstall 'six'.
It is a distutils installed project and thus we cannot accurately determine
which files belong to it which would lead to only a partial uninstall.
sudo pip install six --upgrade --ignore-installed six
sudo pip install --user pyspider  #环境报错
sudo easy_install -U setuptools
sudo pip install ipython

3、pip安装 sudo easy_install pip //这样会安装在系统自带的python2.7的路径下 curl https://bootstrap.pypa.io/get-pip.py | python3 ln -s /Library/Frameworks/Python.framework/Versions/3.6/bin/pip3 /usr/local/bin/pip3

python3.6安装
sudo pip3 --default-timeout=100 install -U tornado
sudo pip3 install ipython

python3     //python登录方式
import tornado
tornado.version -> 5.1.1

ipython    //ipython登录方式
import tornado
tornado.version -> 5.1.1

pip查看已经安装的包
pip freeze

4、软链接 1.查看软链：ls -lih /usr/local/bin/ |grep python3 2.修改软链接：ln –snf 3.创建 find / -name ipython3 ln -s /Library/Frameworks/Python.framework/Versions/3.6/bin/ipython3 /usr/local/bin/ipython3 ln -s /usr/local/bin/ipython3 /usr/local/bin/ipython

sudo ln -nsf  /Library/Frameworks/Python.framework/Versions/3.6/bin/pip3 /usr/local/bin/pip

sudo ln -nsf /Library/Frameworks/Python.framework/Versions/3.6/bin/python3 /usr/local/bin/python

vim ~/.bash_profile
#python
alias python='/usr/local/bin/python'

source ~/.bash_profile

5、tornado http://127.0.0.1:8888 //helloworld http://127.0.0.1:8888/500 //500error http://127.0.0.1:8887/sleep //异步