best text editor for programming Python on a Mac

[Chris]

I have been trying to write a simple Hello World script on my Mac at work with TextEdit.  However, I keep getting this error message:

SyntaxError: Non-ASCII character '\xe2' in hello_world.py on line 1, but no encoding declared; see http://python.org/dev/peps/pep-0263/ for details

I am using TextEdit in plain text mode.  The document was saved in UTF-8, and I still get the error message.  I tried switching to Western ASCII encoding, but once I start typing, I get a message stating that the document can no longer be saved using its original Western (ASCII) encoding.

Any suggestions for a good open source text editor for the Mac out there?  For now, I am going to stick with vim.