When I enter:
port select --list python
This is the result:
Available versions for python:
none
python25 (active)
Python installs to:
/usr/local/bin
/opt/local/bin
/Library/Frameworks/python
...Default python is required by system so best not to mess with it too much. MacPorts Python convenient to use because getting packages so easy.
You can set link as shortcut:
sudo ln -s /opt/local/bin/python /usr/local/bin/ppython
Then from command-line to use MacPorts version:
ppython script.py