Well, Python doesn't have one simple function for this, but you can combine 2 simple functions, list() and join() :)
s = "hello"
# convert the string to a list of characters
lst = list(s) # lst now looks like this: ['h', 'e', 'l', 'l', 'o']
# now combine the list-elements to a string with a whitespace between them
new = ' '.join(lst)