It was not built for the 2 to 3 migration, as there are plenty of great tools already out there for that, like 2to3 itself or futurize. It was built more for cases where we want to make changes to things like function or method signatures, and update both the definition and all call sites, across our entire codebase. It's still a very rudimentary tool at this point, but it was designed in a way that allows us to check in and reuse many components of the codemod, so that we can extract longer term value from these tools.
