Too many resource exist checks

[wachsylon]

slkspec/slkspec/core.py

Line 256 in a52124a

self._retrieve_items(items)

[neumannd]

@observingClouds Can we generally replace this type list of variable items by set? I don't see a reason why a list is needed there. I would need to update _retrieve_items and at least one helper function.

[observingClouds]

I do not see any immediate issue of items being of type set either.

[neumannd]

@observingClouds I set up an update to slkspec (#53) which includes @wachsylon change (#52) plus a fix for an issue which @florianziemen and @xabipedru reported via email. Additionally, it depends on the most recent pyslk release.

[neumannd]

I need to do two manual checks later today. After that, the PR is OK from my side.

[neumannd]

Manual checks were run and a few modifications implemented. @observingClouds Do you have any comments?

[observingClouds]

LGTM

[neumannd]

merged #53