This program is correct or not

Question

letters =["a","b"]
digits = ["1","2"]

def(x)
return ("".join(x))
print(f(letters),f(digits),sep="")

This program generate error and I don't know why

Answer 1

Error is here def f(x):
^ ^

Answer 2

Also you can change
print(f(letters),f(digits),sep="")
To
print(f(letters+digits))

Answer 3

Thanks 😆