Please read the pinned thread and format the code and data properly so that we can properly read and understand it.
The best way to check that your code is correct is to try it. This means you need to know what the answer is for some sample input; run the code with that input; and see if you get the correct answer. (Or at least: when you look at the output, you should be able to tell if it’s wrong.) The next steps are to automate this (using a testing framework such as pytest), and to come up with thorough tests that cover everything that seems like it could go wrong.
When you show code, please include any necessary import statements; and if you are showing terminal output from the code it’s a good idea to format the output the same way (but in a separate block, so it won’t be confused for code). By “statforecast library” I assume you mean this one; it’s good to say these things up front.