To run a python function you do need to write one line of VBA code and you also need a vba file that comes with the package so although its not very much to add on the VBA side the title here seems a bit misleading.
From what I gather watching the video, you only need the xlwing.bas module and the supporting VBA code if you plan to invoke python from within the Excel file. If you're only manipulating an Excel file with Python externally, which was covered in the beginning of the video, it doesn't appear you need the module and VBA code.