py-coverage integrates with Ned Batchelder's code coverage tool for Python
(http://nedbatchelder.com/code/coverage/). After coverage data has been
gathered, this plugin can be used to retrieve the results and present them in
the relevant buffers.

Source lines lacking coverage ("missing") may be indicated by directly
highlighting the lines or by populating the quickfix or location lists. The
function that retrieves the line numbers is also provided for low-level
access.