solution

app/main.py

@@ -9,7 +9,8 @@ def __init__(self, name: str, health: int = 100) -> None:
             Animal.alive.append(self)
 
     def __repr__(self) -> str:
-        return f"{{Name: {self.name}, Health: {self.health}, Hidden: {self.hidden}}}"
+        return (f"{{Name: {self.name}, "
+                f"Health: {self.health}, Hidden: {self.hidden}}}")
 
     @classmethod
     def update_alive(cls) -> None:
@@ -27,5 +28,3 @@ def bite(self, prey: "Animal") -> None:
             prey.health -= 50
             if prey.health <= 0:
                 Animal.update_alive()
-
-