[Tutor] quick question about threads

[nephish]

Hey there, i have a program written in python that uses four threads
that run all at the same time. Now i want to add a new thread with the
same basic structure (threading.thread) that will run only when needed.
This one will not run in a loop, it will just run once and quit.
So, i may need this to be running several times at once because it will
have a 15 second delay written into it.
My question is, after the script is done, will it be safe ? i mean, over
the course of a few days, it may run this thing a few hundred times. if
it is simple like this

threading.thread
	print 'here is something to say'
	time.sleep(15)
	print 'here is something else'

do i need to include a special command to kill the thread, or will it
just finish and everything will be ok then ?

thanks for any tips.
shawn