def cat_twice(part1, part2) :
part1 = 'tata'
part2 = 'titi'
cat = part1 + part2
print(cat_twice())
cat_twice() missing 2 required positional arguments: 'part1' and 'part2'
part1 = 'tata'
part2 = 'titi'
def cat_twice(part1, part2) :
cat = part1 + part2
return cat
print(cat_twice(part1,part2))