What did you do?

>>> import ujson
>>> ujson.dumps({True: 1, False: 2, None: 3})
'{"True":1,"False":2,"null":3}'

What did you expect to happen?

I expected bool values to be serialized as lower-case strings "true" and "false" as standard in JSON. This is what happens with the standard json library:

>>> import json
>>> json.dumps({True: 1, False: 2, None: 3})
'{"true": 1, "false": 2, "null": 3}'

Note that None did produce the expected lower-case "null" value.

What actually happened?

The strings were capitalized, which suggests that they were produced by Python's str or repr.

What versions are you using?

• OS: Debian 11
• Python: 3.9.16
• UltraJSON: 5.8.0