(fix/doc) Move the Python example a little further in README (#970)

Author: lboue

README.md

@@ -246,7 +246,26 @@ When the start_listening command is issued, the server will dump all existing no
 
 **Send a command**
 
-Because we use the datamodels of the Matter SDK, this is a little bit more involved. Here is an example of turning on a switch:
+Here is an example of turning on a switch (OnOff cluster)
+
+```json
+{
+  "message_id": "example",
+  "command": "device_command",
+  "args": {
+    "endpoint_id": 1,
+    "node_id": 1,
+    "payload": {},
+    "cluster_id": 6,
+    "command_name": "On"
+  }
+}
+```
+
+**Python script to send a command**
+
+Because we use the datamodels of the Matter SDK, this is a little bit more involved.
+Here is an example of turning on a switch:
 
 ```python
 import json
@@ -275,21 +294,6 @@ message = {
 
 print(json.dumps(message, indent=2))
 ```
-
-```json
-{
-  "message_id": "example",
-  "command": "device_command",
-  "args": {
-    "endpoint_id": 1,
-    "node_id": 1,
-    "payload": {},
-    "cluster_id": 6,
-    "command_name": "On"
-  }
-}
-```
-
 You can also provide parameters for the cluster commands. Here's how to change the brightness for example:
 
 ```python