The solution to exercise 3 on strings is not strictly correct:

I provide a solution that is

my_string.split()

One might also think of the following solution that could also work:

my_string.split(" ")

However, those two approaches work differently with an empty string:

"".split()  # returns an empty list []
"".split(" ")  # returns a list with an empty string [""]

We should either adapt the description or change solution to .split(" ").