It's not really a useful method and bloats the interface. The documentation already shows the intricacies of using it with recurse=True or recurse=False.

It's more explicit to replace it with

1. batch.is_empty() -> len(batch.get_keys()) == 0
2. batch.is_empty(recurse=True) -> len(batch) == 0

Solving this means using the IDE's find usages, applying the above replacements, and removing is_emtpy from Batch and BatchProtocol