Python loop to run after n minutes from start time

I am trying to create a while loop which will iterate between 2 time objects, while datetime.datetime.now().time() <= datetime.datetime.now() +relativedelta(hour=1): but on every n minutes or second interval. So if the starting time was 1:00 AM, the next iteration should being at 1:05 AM with n being 5 mins. So the iteration should begin after 5 mins of the start time and not for example, from the end of an iteration, which is the case when using sleep. Could you please advise how this could be accomplished?

A possible solution to this was from here: write python script that is executed every 5 minutes

import schedule 
import time 

def func():
    print("this is python")

schedule.every(5).minutes.do(func)
while True:
    schedule.run_pending()
    time.sleep(1)

With this, the start time has to be 1 am. Secondly, what if the program needs to run say 5 min + 1. In that case a 6 min interval wont work.

from Python loop to run after n minutes from start time