Refactor prod_validators.py such that there is one validator module per model module in core/storage/.

List of model categories

• activity @ankita240796 (#10416)
• audit
• base_model @ankita240796 (#10360)
• classifier
• collection
• config
• email
• exploration
• f

Regarding the drop down menu, yes, I think it would be better to only have the "task cell" option visible for markdown cells.

The documentation asserts this too "If you select the “Manually graded task” option (available for markdown cells), the nbgrader extension will ..."

Currently it seems like TAs write their own scripts to assign problems to each other. We should do this for them, and have a "Assign Graders" button that they can use.

We've the e2e tests within the test directory.

• teachcode -h || teachcode --help (@rishabhKalakoti )
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• `te