Add get_available_cats() method to tutorial.py

[jukent]

Change Summary

Adding a get_keys() method to the tutorial.py module. This will help with the documentation by listing all of the available dataset catalogs to then choose from before calling tutorial.get_url().

Is it necessary to add a long-name associated with each of these keys?

Also corrects a spelling error on "catalog" in tutorial.py and adds a check that the tutorial_catalogs input kwarg is a dictionary.

Related issue number

The need for this arose while working on #456

Checklist

• Unit tests for the changes exist
• Tests pass on CI
• Documentation reflects the changes where applicable

[jukent]

Both get_url and get_keys allow the user to pass in their own dictionary of keys mapping to urls in the kwargs, instead of just the tutorial_catalog dictionary. There aren't tests checking for a bad dictionary input though. --- This is now done.

[andersy005]

This looks solid to me 👍🏽

thank you @jukent!

[andersy005]

Both get_url and get_keys allow the user to pass in their own dictionary of keys mapping to urls in the kwargs, instead of just the tutorial_catalog dictionary.

my latest change restricts this to a default dict of values so as to reduce the complexity of the codebase. we can add this feature later when there's a demand for it.