例如，我在一個名為tf_14的vertualenv環境中(no-site-package)安裝了一個contextlib2包
(tf_14) novak@novak-ZBook15G2:~/Carnd3/kinshuk4_tl_detection/CarND-TrafficLight-Classification$ pip install contextlib2
Collecting contextlib2
Downloading https://files.pythonhosted.org/packages/a2/71/8273a7eeed0aff6a854237ab5453bc9aa67deb49df4832801c21f0ff3782/contextlib2-0.5.5-py2.py3-none-any.whl
Installing collected packages: contextlib2
Successfully installed contextlib2-0.5.5
使用which xxx來查看
使用pip show指令來查看
(tf_14) novak@novak-ZBook15G2:~/Carnd3/kinshuk4_tl_detection/CarND-TrafficLight-Classification$ pip show contextlib2
Name: contextlib2
Version: 0.5.5
Summary: Backports and enhancements for the contextlib module
Home-page: http://contextlib2.readthedocs.org
Author: Nick Coghlan
Author-email: ncoghlan@gmail.com
License: PSF License
Location: /home/novak/tf_14/lib/python2.7/site-packages
Requires:
Required-by: