Update app.py

app.py

@@ -8,7 +8,6 @@ import gymnasium as gym
 from gymnasium import spaces
 import numpy as np
 from PIL import Image
-from gymnasium.vector import SyncVectorEnv
 import gradio as gr
 
 # Environment Variables
@@ -136,7 +135,7 @@ def optimize_signal_rl(congestion_level):
         congestion_level = congestion_map.get(congestion_level, 5) if isinstance(congestion_level, str) else congestion_level
 
         # Create environment
-        env = SyncVectorEnv([lambda: TrafficSimEnv(congestion_level)])
+        env = DummyVecEnv([lambda: TrafficSimEnv(congestion_level)])
 
         # Initialize PPO model
         model = PPO("MlpPolicy", env, verbose=0)