Store a set in a dictionary's value

[bowlofred]

In line 4 you're creating a single set and trying to use it later. But every team need their own set. So you have to create it when it doesn't exist, and you don't need to keep track of it outside the dict.

In line 7, your dict value should already be a set. You want to modify that value (with add() method, not replace the value with something else.

Inn line 9, you need to create a (new) set, not reference a previously created one.