If the player touches the coin, we want the coin to change to a new random position. We can detect collisions using an if statement and the colliderect() function. This is part of our game logic, so this code should be placed inside the update() function.
if player.colliderect(coin): coin.x = random.randint(0, 800) coin.y = random.randint(0, 600)
Basically, what this code says is... "If the player collides with the coin, set a new random x and y position for the coin."