That’s not what the article says. The last paragraph:

  if (cell[0][0] == cell[1][1] == cell[2][2]) {
      return Winner
  }

> Well the code is indeed correct . Well done, Python… for finding yet another way to confuse us all.

The code is incorrect: if all entries are '-' there is no winner. Even ignoring the braces…

To be fair to parent I read the whole thing and also missed that.