In your description of the get command, where you say

>>

get foo

Again, the server will return the value of the key, in this case “foo”.

<<

I’m sure you meant to say

>>

get foo

Again, the server will return the value paired with the key, in this case “bar”.

<<

Similarly for the set command. Later in the article, your example implementation of set and get correctly return the value, “bar”.