Rereformat callbacks.py

We really need lint-staged here.

Author: Twixes

posthog/ai/langchain/callbacks.py

@@ -21,14 +21,7 @@
 from langchain.callbacks.base import BaseCallbackHandler
 from langchain.schema.agent import AgentAction, AgentFinish
 from langchain_core.documents import Document
-from langchain_core.messages import (
-    AIMessage,
-    BaseMessage,
-    FunctionMessage,
-    HumanMessage,
-    SystemMessage,
-    ToolMessage,
-)
+from langchain_core.messages import AIMessage, BaseMessage, FunctionMessage, HumanMessage, SystemMessage, ToolMessage
 from langchain_core.outputs import ChatGeneration, LLMResult
 from pydantic import BaseModel