Sending a decimal.Decimal in a dwollav2 request body failed unless the optional simplejson package happened to be installed — and simplejson wasn't listed as a dependency anywhere. The reporter argued a JSONEncoder subclass handles decimals fine and simplejson offers no benefit on modern Python; a PR was submitted. The maintainer published the fix in dwollav2 v2.3.0, which serializes Decimal values without needing simplejson.