Should `OffTargetDetector.mappings_of()` return a `dict[Primer, BwaResult]` instead of `dict[str, BwaResult]`?

[emmcauley]

Context: OffTargetDetector.mappings_of() currently returns dict[str, BwaResult] where the key is the sequence of bases of the primer. It may be more natural to return the full Primer object as the key instead of just the bases.

[msto]

We'll need to make Primer hashable in order to do so (adding eq=True to the dataclass decorator should be sufficient)

[tfenne]

This would make a lot of sense to me, since my first question when I looked at that code was "why are we returning a dict keyed on strings instead of primers".