Matt

Results 2 issues of Matt

This works towards closing #337 by making the implementations of `From for Duration` and `From for std::time::Duration` lossless. Thank you!

This PR migrates `seqscore` from `attrs` to `pydantic` in order to take advantage of `pydantic`'s built-in serialization utilities, in addition to `pydantic` being a common interface for libraries in the...