fix: use threading lock instead of boolean

index.py

@@ -56,18 +56,15 @@
 # }
 
 global save_lock
-save_lock = False
+save_lock = threading.Lock()
 def save():
     global save_lock
-    while save_lock:
-        time.sleep(0.1)
-
-    save_lock = True
+    save_lock.acquire()
 
     with open(const.FETCHED_JSON, "w", encoding="utf8") as f:
         json.dump(fetched, f, indent=4, ensure_ascii=False)
 
-    save_lock = False
+    save_lock.release()
 
 if os.path.isfile(const.FETCHED_JSON):
     with open(const.FETCHED_JSON, encoding="utf8") as f:
@@ -274,4 +271,4 @@ def clear_chat():
     if const.CHAT_DIR:
         chat_expiry_task.stop()
         for video_id in chats:
-            chats[video_id].stop()
+            chats[video_id].stop()