Every Monday a dog goes into a small supermarket with a basket in his mouth. Inside the basket is a shopping list and a wallet.
Maria, who owns the store, reads the list, puts the items in the basket, takes the money from the wallet and leaves the bill. The dog then runs off.
One day, Maria decides to follow the dog. She wants to meet the owner and ask how the dog was trained to do such amazing things.
She follows the dog to an old house. The dog puts down the basket at the door and rings the bell with his nose.
A man opens the door and starts yelling and screaming at the dog. He goes on and on. Maria sees that the dog is very irritated.
"Stop that!" shouts Maria. "What are you doing? That's the smartest dog I've ever seen!"
"Smart? Ha!" laughs the man. "That's the third time this week he's forgotten his keys."