Hi -- thanks for the report! You haven't given us many details here, but I think this is intentional behaviour, not a bug -- this was changed in Issue37324. Importing `Mapping` (along with many other names) directly from `collections`, instead of from `collections.abc`, has been deprecated since Python 3.3, and was removed in Python 3.10. So instead of writing `from collections import Mapping`, simply write `from collections.abc import Mapping`, and you should find that no error is raised.