Even after saving and the whole assingment passing correctly i am getting this error because of whhich i cant proceed

Failed test case: history has incorrect type.
but got:
<class ‘NoneType’>.

i am getting this error even after several attempts cant get through this
can someone please tell me what to do and how to

Could you please share the code you are using
Pls share the code in both .ipynb and .pdf format


Thanks for reaching out.
I guess you forgot to replace the “None” with appropriate parameters/values or you forgot to save your file before submitting.
This error comes when the appropriate value is not passed and the grader reads “None”.

Nevertheless, I would like to see your notebook to give you a specific answer for your specific problem.So can you kindly send your notebook via message. Click on my name, you will get an option for message.

With regards,
Nilosree Sengupta