The idea is whenever the sprite collides with an enemy, it "explodes".
To achieve this explosion effect, the sprite should increase in size and decrease in opacity. However, when the following code is activated, it returns an "out of memory" error.
self.scale *= 1.25
self.image = pygame.transform.scale(self.imgza, (round(self.scale), round(self.scale)))
#self.imgza is the PNG/Image of the sprite.
(The game itself is over 200 lines of code, so I will not paste it in here)
For further debugging, this is the error I received
self.image = pygame.transform.scale(self.imgza, (round(self.scale), round(self.scale)))
pygame.error: Out of memory