Fix displaying of new PEPs in python-news

[wookie184]

Currently we only send new PEP updates to #mailing-lists if they were "created" on the same day that the bot is checking for them.

bot/bot/exts/info/python_news.py

Lines 116 to 120 in ea0b227

	if (
	pep_nr in pep_numbers
	or new_datetime.date() < date.today()
	):
	continue

This does not work in most cases, as when PEPs are created is not the same as when they are published.
https://peps.python.org/pep-0001/#pep-header-preamble

The Created header records the date that the PEP was assigned a number

The number is usually assigned quickly after the PR to https://github.com/python/peps is created, but then the PR is reviewed which means it can be a while before it's actually merged and becomes visible. The difference can be fairly big (e.g. python/peps#2620).

We can fix this by extending the check if it's in the last month (maybe last 2 months). The only issue I see with this is that in development people might get a few peps sent in a row when they first start up, but this seems pretty minor.

[mbaruh]

I'm somewhat struggling with the overall logic of that function. If we're keeping track of what PEPs are already shown in the channel, why do we need any date validation?

It also doesn't seem like there's an exit condition in the loop. Are we just going over the entire feed every time?

[wookie184]

I'm somewhat struggling with the overall logic of that function. If we're keeping track of what PEPs are already shown in the channel, why do we need any date validation?

It shouldn't make a big difference in production, although in dev it prevents you being sent loads of posts when you first start up the bot. The feed only contains the past 10 PEPs so it would be fine without the validation, although a generous time check would also be fine imo.

It also doesn't seem like there's an exit condition in the loop. Are we just going over the entire feed every time?

Yeah