diff --git a/ereuse_devicehub/resources/models.py b/ereuse_devicehub/resources/models.py
index 74e1e6b4..d6fafc78 100644
--- a/ereuse_devicehub/resources/models.py
+++ b/ereuse_devicehub/resources/models.py
@@ -36,8 +36,11 @@ class Thing(db.Model):
         self.created = kwargs.get('created', datetime.now(timezone.utc))
         super().__init__(**kwargs)
 
+
 def on_update_time(mapper, connection, thing_obj):
+    """ This function update the stamptime of field updated """
     thing_obj.updated = datetime.now()
 
 def update_timestamp(thing_obj):
+    """ This function launch a event than listen like a signal when some object is saved """
     event.listen(thing_obj, 'before_update', on_update_time)