When trying to "import cv" in python I get: "ImportError: No module named cv". This question has appeared in many forms, but I haven't found the answer that helps.
On my Mac OS X Lion, among many other ports, I have run:
sudo port install python27
sudo port install opencv +python27
port select python
port installed opencv
I had this same problem. It looks like a (maybe?) bug with the OpenCV install script for 2.3.1a. It will not create the Python bindings unless NumPy is already installed.
To fix it:
sudo port uninstall opencv sudo port install py27-numpy sudo port install opencv +python27
That worked for me! I found this by doing some Googling, and the correct answer was here: wbarczynski.org/wp/2011/11/25/opencv-with-py-bindings-on-mac-with-macports-intall-numpy-first/