How to process txt file in python on telegram bot?

Question

Python

I am creating a telegram bot that will check the txt file, its contents. I need the bot to download and save it, and then check its contents and work with it, and also when a new file is sent, the old one is automatically erased. Yes, the problem is that get_file works strangely, or its use is not formulated correctly in Internet resources. I would like someone to explain to me how I can realize my idea, thanks in advance.