better lazy loading via class

app.py

@@ -50,20 +50,27 @@ h1 {
 
 rng = np.random.default_rng(0xDEADBEEF)
 
-model: AHOY = None
+class SeaVisionModel:
+    def __init__(self, model_name="ahoy-RGB-b2"):
+        self.model_name = model_name
+        self.model = None
+
+    def get_model(self):
+        if self.model is None:
+            self.model = load_model(self.model_name)
+        return self.model
+
+    def run_inference(self, image):
+        model = self.get_model()
+        results = model(image)
+        return results.draw(image, diameter=4)
+
+vision_model = SeaVisionModel()
 
 @spaces.GPU
 def inference(image):
     """Run inference on image and return annotated image."""
-    global model
-    if model is None:
-        # lazy load model
-        model = load_model("ahoy-RGB-b2")
-    results = model(image)
-    return results.draw(image, diameter=4)
-
-
-model = load_ahoy()
+    return vision_model.run_inference(image)
 
 # Flagging
 dataset_name = "SEA-AI/crowdsourced-sea-images"