feature：积分交易功能上线

point_trade/main.py

@@ -192,7 +192,7 @@ class PointTrade:
                     SELECT id, wx_id, wx_nick_name, points FROM t_sign_record 
                     WHERE wx_nick_name = %s AND group_id = %s
                 """, (wx_nick_name, group_id))
-                return self.cursor.fetchone()
+                return cursor.fetchone()
 
     def _update_user_points(self, user_id, new_points):
         """