[antod]

In terms of web debugging instead of general code debugging tools mentioned by others, the common Python frameworks have toolbars based on Armin's Werkzeug one:

http://werkzeug.pocoo.org/docs/dev/debug/

eg...

For Pyramid: http://docs.pylonsproject.org/projects/pyramid-debugtoolbar/...

For Flask: http://flask-debugtoolbar.readthedocs.org/en/latest/

For Django: https://github.com/django-debug-toolbar/django-debug-toolbar

I have no idea how well they compare to equivalent Rails tools though.