updated usage section in readme

README.md

@@ -24,5 +24,14 @@ model-index:
   This is a trained model of a **PPO** agent playing **LunarLander-v2** using the [stable-baselines3 library](https://github.com/DLR-RM/stable-baselines3).
   
   ## Usage (with Stable-baselines3)
-  TODO: Add your code
-  
+```
+  from typing import Callable
+
+  def linear_schedule(initial_value: float) -> Callable[[float], float]:
+      def func(progress_remaining: float) -> float:
+          return progress_remaining * initial_value
+  
+      return func
+  
+  model = PPO(policy="MlpPolicy", env=env, verbose=1, n_epochs=10, learning_rate=linear_schedule(0.005), n_steps=1500)
+```