From fbc83dfdbbc10cf55e4d3501a8b4f846efde54d9 Mon Sep 17 00:00:00 2001
From: shibuiwilliam <shibuiyusuke@gmail.com>
Date: Tue, 8 Aug 2023 03:02:19 +0900
Subject: [PATCH] Fix/abstract add message (#8856)

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---
 libs/langchain/langchain/schema/memory.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libs/langchain/langchain/schema/memory.py b/libs/langchain/langchain/schema/memory.py
index 46da7504b2..fe1b784440 100644
--- a/libs/langchain/langchain/schema/memory.py
+++ b/libs/langchain/langchain/schema/memory.py
@@ -107,14 +107,14 @@ class BaseChatMessageHistory(ABC):
         """
         self.add_message(AIMessage(content=message))
 
-    # TODO: Make this an abstractmethod.
+    @abstractmethod
     def add_message(self, message: BaseMessage) -> None:
         """Add a Message object to the store.
 
         Args:
             message: A BaseMessage object to store.
         """
-        raise NotImplementedError
+        raise NotImplementedError()
 
     @abstractmethod
     def clear(self) -> None: