Update how-to-setup-rbac.md

Adding Cosmos Python ClientSecretCredential implementation now that it is live

Author: simorenoh

articles/cosmos-db/how-to-setup-rbac.md

@@ -350,6 +350,7 @@ The way you create a `TokenCredential` instance is beyond the scope of this arti
 - [In .NET](/dotnet/api/overview/azure/identity-readme#credential-classes)
 - [In Java](/java/api/overview/azure/identity-readme#credential-classes)
 - [In JavaScript](/javascript/api/overview/azure/identity-readme#credential-classes)
+- [In Python](/python/api/overview/azure/identity-readme?view=azure-python#credential-classes)
 
 The examples below use a service principal with a `ClientSecretCredential` instance.
 
@@ -397,6 +398,18 @@ const client = new CosmosClient({
 });
 ```
 
+### In Python
+
+The Azure Cosmos DB RBAC is currently supported in the [Python SDK V4.3.0b4](sql-api-sdk-python.md).
+
+```python
+aad_credentials = ClientSecretCredential(
+    tenant_id="<azure-ad-tenant-id>",
+    client_id="<client-application-id>",
+    client_secret="<client-application-secret>")
+client = CosmosClient("<account-endpoint>", aad_credentials)
+```
+
 ## Authenticate requests on the REST API
 
 When constructing the [REST API authorization header](/rest/api/cosmos-db/access-control-on-cosmosdb-resources), set the **type** parameter to **aad** and the hash signature **(sig)** to the **oauth token** as shown in the following example: