#5: Prefer tempora to jaraco.timing.
#4: Consolidate acquire, release, and is_locked behavior into LockBase. Atomically remove lock attribute during release. Use jaraco.functools 1.16 for the retry logic.
Update package skeleton.
Correct badges in README.
#2: Suppress errors in the rare condition where the lockfile has disappeared between the release of the lock and the deletion of the file.
#3: Moved project to Github.
Re-use Stopwatch class from jaraco.timing.
Dropped support for Python 2.6.