add message when deleting user or stock

model.py

@@ -899,6 +899,11 @@ def delete_user(user_id):
         WHERE used_by_user_id = ?
         ''', (user_id,))
 
+    cursor.execute('''
+        INSERT INTO news(title)
+        VALUES (CONCAT ((SELECT username FROM users WHERE rowid = ?), ' retired.'))
+        ''', (user_id,))
+
     cursor.execute('''
         DELETE FROM users
         WHERE rowid = ?
@@ -926,6 +931,11 @@ def delete_ownable(ownable_id):
         AND amount = 0
         ''', (ownable_id,))
 
+    cursor.execute('''
+        INSERT INTO news(title)
+        VALUES (CONCAT ((SELECT name FROM ownables WHERE rowid = ?), ' can not be traded any more.'))
+        ''', (ownable_id,))
+
     cursor.execute('''
         DELETE FROM ownables
         WHERE rowid = ?