I have my own package in python and I am using it very often. what is the most elegant or conventional directory where i should put my package so it is going to be imported without playing with PYTHONPATH or sys.path?
What about site-packages for example?
/usr/lib/python2.7/site-packages.
Is it common in python to copy and paste the package there ?
On my Mac, I did a sudo find / -name "site-packages". That gave me a few paths like /Library/Python/2.6/site-packages, /Library/Python/2.7/site-packages, and /opt/X11/lib/python2.6/site-packages.
So, I knew where to put my modules if I was using v2.7 or v2.6. 
Hope it helps.
Where should I put my own python module so that it can be imported