This really simple bot, @sticker_to_png_bot, allows you to get PNG of any sticker keeping the transparency.
Because every time I want to edit a sticker and add it to my pack I have to: Download the image, look for an online webp converter, wait conversion, save and edit. I'm sure, don't lie, at least one time you wanted to create a funny sticker just to make fun of friends.
Well, even if it's a small bot, I suggest you to start with a virtual environment (if you can you should always do it)
python3 -m venv myenvironment
source myenvironment/bin/activate
You can install modules with our dear pip :)
pip3 install Pillow
pip3 install requests
pip3 install python-telegram-bot