Python site-packages permission denied?

[Shane Neeley]

What do I need to do to successfully install a package onto python so that I can use it as a module? 

I have tried in terminal in the correct directory "python2.7 ./setup.py install" but it says permission denied.

Shanes-MacBook-Pro:seisen-urllib2_file-cf4c4c8 chimpsarehungry$ python2.7.1 ./setup.py install
-bash: python2.7.1: command not found
Shanes-MacBook-Pro:seisen-urllib2_file-cf4c4c8 chimpsarehungry$ python ./setup.py install
running install
running build
running build_py
running install_lib
copying build/lib/urllib2_file.py -> /Library/Python/2.7/site-packages
error: /Library/Python/2.7/site-packages/urllib2_file.py: Permission denied
Shanes-MacBook-Pro:seisen-urllib2_file-cf4c4c8 chimpsarehungry$