enemy:on_custom_attack_received(attack, enemy_sprite) does not allow to call enemy:hurt()
I used "function enemy:on_custom_attack_received(attack, enemy_sprite)" for the sword ("custom" effect for an enemy). Then I try to call "enemy:hurt()" inside that event and nothing happens. (I've used "print" functions and I confirm that that line is being called, but the enemy is not hurt.)