It would be helpful if there was a way to start the timer when it is instantiated, such as t = Timer().start() or t = Timer(now=True).
This can reduce the number of required lines from 3 to 2 which is nice when inserting many timers.
t = Timer().start()
# code block 1
t.stop()
t = Timer().start()
# code block 2
t.stop()
t = Timer().start()
# code block 3
t.stop()
To do this, either .start() would need to return self or a Timer.__post_init__ function would need to if self.now == True.