Add docs/code comments for message-send-flow

app/job/rest.py

@@ -166,10 +166,10 @@ def get_jobs_by_service(service_id):
 
 @job_blueprint.route("", methods=["POST"])
 def create_job(service_id):
-    '''
+    """
     Entry point from UI for one-off messages
     as well as CSV uploads.
-    '''
+    """
     service = dao_fetch_service_by_id(service_id)
     if not service.active:
         raise InvalidRequest("Create job is not allowed: service is inactive ", 403)