python - Better way to find common words in a tuple? -

i completed exercise in found , returned common words between 2 strings in alphabetical order string, separated commas. though able correctly, wondering if there better way. better can defined define it.

def return_common(first, second):     first = first.split(',')     second = second.split(',')     newlist = ",".join(list(set(first) & set(second)))     #newlist = list(newlist)     newlist = newlist.split(',')     newlist = sorted(newlist)     newlist = ",".join(newlist)     return newlist  return_common("one,two,three", "four,five,one,two,six,three") #above returns 'one,three,two' 

the code can shortened(into line) -

def return_common(first, second):     return ",".join(sorted(set(first.split(","))&set(second.split(",")))) 

testing -

>>> return_common("one,two,three", "four,five,one,two,six,three") 'one,three,two'