well, you could easily reduce this 3 lines:
delimiter = ' '
a = delimiter.join(new_list)
return ' '.join(new_list)
for the rest, it is quit an elegant solution, what is the problem?
of course, you could shorten it more. But it doesn't become much simpler then this, your code is nice and clean
you could use
replace(), it will pass the exercise, but if you then want to censor
is then replace changes
th**, and not really nice, since you don't do any coding then.
you could use list comprehension, but hasn't been taught yet.
result = [ x if x != word else "*" * len(word) for x in text.split() ]
but this is not as clean and readable as your code