What's the solution ? even though the test results are correct

There was a problem compiling the code from your notebook. Details:
‘NoneType’ object is not callable

Did you leave any of the “None” statements in the notebook (which you are supposed to replace with your own code)?

You must complete all of the parts of the assignment before you can submit it for grading.

I have finished everything, but when I submit it appears something like that

I presume the name of the notebook file is “C2_W1_Assignment”, “Optimizing Functions of One Variable: Cost Minimization”?

Does your notebook pass all of the tests (and give all of the Expected Output), after you use these two menu commands?

  • “Kernel” → “Restart & clear output”
  • “Cell” → “Run All”

ya, All tests passed

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