fix: update the return type to 'Hash32'

[e3243eric]

What was wrong?

Issue #192

How was it fixed?

Update the return type from bytes to Hash32 for all methods that apply keccak. I explicitly cast the return type of eth_hash.auto.keccak to Hash32 in crypto.py, since its return type is bytes, maybe this should be fixed in eth_hash too.

To-Do

• [x] Clean up commit history

• [x] Add entry to the release notes

Cute Animal Picture

[e3243eric]

Hi @carver, does this fix the issue? I need someone to do a code review. Thanks!

[carver]

I'm no longer an active maintainer on this project, paging @kclowes

[carver]

Note that I did not do a thorough search for all methods that should be updated, so part of the task is to identify all functions that should be updated.

[carver]

Also note that because some projects (especially some of ours) use type checking as part of CI, we typically treat type signature changes as breaking changes.

[e3243eric]

It seems like the newsfragment doesn't have a breaking type. We should update the validate_files.py.

[carver]

Ah yeah, that implies that eth-utils is due for a merge from the latest template