Hi,
Just to be clear, you are looking for reference DFU controller firmware for the Host MCU, in order to upgrade the firmware on the nRF52832。
I also need this feature here. I got a copy of your python code, which is more complicated. The most critical send function inside, there are other functions nested inside. Now I can only develop it myself. I believe this difficulty is very big. What do you think? If it is too difficult, I suggest to my manager, I believe he will cancel this feature.