Reporting cumulative coverage across multiple Python versions

Reporting cumulative coverage across multiple Python versions References I have code that runs conditionally depending on the current version of Python, because I\'m supporting 2.6, 2.7, and 3.3 from the same package. I currently generate a coverage report like this, using the default version of Python: coverage run --source mypackage setup.py test coverage report -m coverage html This is useful but not ideal, as it only reports coverage on Python 2.7. Instead, I would like to generate a cumulative report of the test coverage across 2.6, 2.7, and 3.2. How do I generate a multi-version coverage report? Side note: I\'ve tried putting commands = coverage run --source mypackage setup.py test into my tox.ini for each of py26, py27, py33, but that doesn\'t seem to generate a cumulative coverage report.