diff --git a/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py b/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
index a3ee079d1..4bd0839c2 100644
--- a/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
+++ b/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
@@ -19,11 +19,11 @@ from ipaddress import (
 )
 from typing import Any, Callable, Optional, Union, cast
 from uuid import UUID
-from zoneinfo import ZoneInfo
 
 import msgpack  # type: ignore[import-untyped]
 from langchain_core.load.load import Reviver
 from langchain_core.load.serializable import Serializable
+from zoneinfo import ZoneInfo
 
 from langgraph.checkpoint.serde.base import SerializerProtocol
 from langgraph.checkpoint.serde.types import SendProtocol