text: Title: `test_resources.py` is too large and can be broken up
  Body: The `test_resources.py` module is too large (~1.8k lines).  It could be broken up into its own package, with sub-modules.
  
  Additionally `ModelResourceTest` test case is too large and should be broken up.
  
  For example:
  
  ```
  test_resources/
    test_modelresource/
      test_export.py
      test_import.py
   ...
  ```
  
  
  