Run in a repository to see per-contributor statistics about who last touched how many lines.
With an option, generate a report that can be visited in an Emacs compilation buffer to step through contribution bands.
With a different option, report commit counts by author.
A simple Python 3 script. Just download it and go.
"make" in the project directory builds the documentation. "make install" as root installs the code and documentation. "make check" runs the test suite.