Add finalize function to processor

pytchat/core_async/livechat.py

@@ -325,6 +325,7 @@ class LiveChatAsync:
             self._pauser.put_nowait(None)
         self._is_alive = False
         self._buffer.put_nowait({})
+        self.processor.finalize()
         
     def _task_finished(self):
         '''

pytchat/core_multithread/livechat.py

@@ -316,6 +316,7 @@ class LiveChat:
         self._is_alive = False
         self._buffer.put({})
         self._event.set()
+        self.processor.finalize()
 
     def _task_finished(self):
         '''

pytchat/processors/chat_processor.py

@@ -21,3 +21,10 @@ class ChatProcessor:
             }
         '''
         pass
+
+    def finalize(self, *args, **kwargs):
+        '''
+        Interface for finalizing the process.
+        Called when chat fetching finished.
+        '''
+        pass