Remove unnecessary variable

fw.py

@@ -17,7 +17,6 @@ TENANT = getenv('TENANT')
 GROUP_NAME = getenv('GROUP_NAME')
 REGION = getenv('REGION')
 
-subscription_id = SUBSCRIPTION_ID
 credentials = ServicePrincipalCredentials(
     client_id = CLIENT_ID,
     secret = SECRET,
@@ -26,7 +25,7 @@ credentials = ServicePrincipalCredentials(
 
 network_client = azure.mgmt.network.NetworkManagementClient(
     credentials,
-    subscription_id
+    SUBSCRIPTION_ID
 )
 
 celery = Celery('fw',)