Issues with installing Social Engineering Toolkit (S.E.T)
In a vanilla Lion installing Social Engineering Toolkit works if you use

git clone https://github.com/trustedsec/social-engineer-toolkit
cd social-engineer-toolkit
sudo python setup.py install


(which will install some necessary tools/libraries to /Library/Python/2.7/site-packages).

After "installing" the toolkit use sudo ./setoolkit to start the SE Toolkit.

Here are some env variables:

$ python --version
Python 2.7.1
$ which python
/usr/bin/python
$ python -c "import sys;print(sys.path)"
['', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages', '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old', '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload', '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC', '/Library/Python/2.7/site-packages']
$ echo $PATH
/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin




You probably installed Python 3.5 – which is not included in OS X Lion – and modified some env variables. Without further informations your SE Toolkit install can't be salvaged.