The assignment should be correct , but this issue still exists for more then 2 days?
Grader Error: Grader feedback not found
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First try using the forum search tool for the words “grader feedback not found”.
There are lots of threads about this.
At the start of the notebook there’s:
**Important Note on Submission to the AutoGrader**
Before submitting your assignment to the AutoGrader, please make sure you are not doing the following:
1. You have not added any extra print statement(s) in the assignment.
2. You have not added any extra code cell(s) in the assignment.
3. You have not changed any of the function parameters.
4. You are not using any global variables inside your graded exercises. Unless specifically instructed to do so, please refrain from it and use the local variables instead.
5. You are not changing the assignment code where it is not required, like creating extra variables.
If you do any of the following, you will get something like, Grader Error: Grader feedback not found (or similarly unexpected) error upon submitting your assignment. Before asking for help/debugging the errors in your assignment, check for these first. If this is the case, and you don't remember the changes you have made, you can get a fresh copy of the assignment by following these instructions.
This clearly mentions if you do any of the listed things you will run into
Grader Error: Grader feedback not found.
Please make sure you are not doing any of these listed things.