Steam API - How to get information about the lots of the trading platform in python?

Question

Steam

I decided to make a "small" parser of the information I need on the lots of the Steam trading platform for operating with it in the future. Since, I have looked at a lot of information on how to do this, I have not found anything sweaty or found, but without a proper explanation.
Let's take an example https://question-it.com/questions/4398755/steam-ma... here a request to the TP is formed with a clear explanation for this situation. I need more detailed explanation some documentation.
I do not consider the option with the official api, since there are no details with the TP (steamworks).

I chose Python, because this language is much closer to my heart and I understand it more (in any case, it will be possible to rewrite it).

Procedure:
1. This is to do a complete parsing of all lots for the game, let's conditionally take pubg ( id 578080 ).
2. According to the required algorithm, I select items (well, let's say in an array)
3. For the selected items, I collect complete information, that is, the price of an auto purchase, just purchases, sales, in a raging one, an individual item id, float, etc. is possible.
And of course these requests should be generated automatically according to a given model and saved all this in the database (this is the easiest part)

That's all I need to create a steam bot. Yes, I am a sick person who amuses himself in this way.
I saw that there are already similar solutions, but there are so many huge projects (several thousand lines) that I will understand them until the second precedence and it will be much easier and more interesting for me to figure it out myself.

I considered the option "no reception against scrap" in the form of bs4, but this is the extreme option to which I will come, in case of no luck with api or its like.

I will forgive you to give me a mechanism, how to do it or become it, guides and other information.