doc: Example for port description, VID and PID

Author: nbuchwitz

README.md

@@ -60,6 +60,27 @@ print("Get port 1-1.1 status")
 print(port.status)
 ```
 
+## Device details
+
+```python
+import uhubctl
+
+hubs = uhubctl.discover_hubs()
+
+for hub in hubs:
+    print(f"Found hub: {hub}")
+
+    for port in hub.ports:
+        print(f"   Found port: {port}")
+        
+        # You can use the optional argument `cached_results=False` for each of 
+        # these 3 methods in order to invalidate the internal cache,
+        # which is used for performance reasons
+        print(f"      Description: {port.description()}")
+        print(f"      Vendor ID: {port.vendor_id()}")
+        print(f"      Product ID: {port.product_id()}")
+```
+
 # FAQ
 
 ### How can I specify the path to ´uhubctl´