chlorine kills bacteria in a couple of minutes.
Not sure I agree - back when I took the Bio-Hazards course, we were taught the opposite, chlorine"kills" a small percentage of pathogens (including bacteria) in a few minutes, but exposure times of 10 -20 min (& 60min) are required for more rigorous sanitation ... if you just want to put bacteria into a "static" phase, that is more easily done.
Chorine remains the "sterilizing agent of choice" only because it is cheap, CHEAP, cheap ... the by-products are also well "understood" (researched, identified etc) so drinking water treatment continues to rely heavily on chlorine ... at one point, chloramine was heavily promoted, but that fell on the wayside when the by-products were found to be far-ranging, it's also (often) more $$ than chlorine so it's still in limited use (UK & some areas of the US embraced it, other countries ruled against it's use re certain by-products).
Depending on your water supplier, chlorine levels are rather lower at the point of use than at point of "sanitation" (local water system installed treatment stations as various points on the line to enable better control & reduce chlorine levels at line "start").
Adding water back with a good amount of splashing/aeration helps to offset incoming chlorine levels (not sure if this is due to increased aeration or "offed" chlorine, likely synergy).
It's recommended to leave filters running with "splash" when adding tap water directly to tank with a Python (sorry don't recall if that was in the "Use" videos that ran non-stop at local shops that sold the Python system - or if it came up in discussions ...)
If you're adding Prime it was recommended by Seachem (back when GM was on the forums) to add in a dose for entire tank volume at the start of refill, then, possibly a 2nd dose upon water refill completion (S had done considerable research before bringing this compound to market) as it was possible for Prime to be significantly neutralized by various components in tank, so if you had a situation of loads of organics in tank + maximum allowed chlorine levels, additional dosing might be needed to maintain minimal chlorine levels.