How to insert string in each match using RegEx iterator

[504crank at gmail.com]

By what method would a string be inserted at each instance of a RegEx
match?

For example:

string = '123 abc 456 def 789 ghi'
newstring = ' INSERT 123 abc INSERT 456 def INSERT 789 ghi'

Here's the code I started with:

>>> rePatt = re.compile('\d+\s')
>>> iterator = rePatt.finditer(string)
>>> count = 0
>>> for match in iterator:
	if count < 1:
		print string[0:match.start()] + ' INSERT ' + string[match.start
():match.end()]
	elif count >= 1:
		print ' INSERT ' + string[match.start():match.end()]
	count = count + 1

My code returns an empty string.

I'm new to Python, but I'm finding it really enjoyable (with the
exception of this challenging puzzle).

Thanks in advance.