Assignment Week 1 NMT with Attention not being graded at all

The Week 1 assignment is not being graded at all when submitted just says the Grader has failed.

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Here’s how I got around this error - I renamed the notebook file to something like ‘C4_W1_Assignment - Original.ipynb’, then clicked through to jupyter and created a new blank notebook. I named this blank file ‘C4_W1_Assignment.ipynb’ and copied all the code cells from the original into this file. Then clicked ‘Submit Assignment’, everything passed.