test local_device_count

Author: xuanguang-li

lectures/ar1_turningpts.md

@@ -67,6 +67,9 @@ import arviz as az
 sns.set_style('white')
 colors = sns.color_palette()
 key = random.PRNGKey(0)
+
+print(f"Available devices: {jax.local_device_count()}")
+print(f"Device list: {jax.devices()}")
 ```
 
 ## A Univariate First-Order Autoregressive Process