From 865a21938c0eeeca76943c57422630675fb309f9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1=C5=A1=20Dvo=C5=99=C3=A1k?= <toomas2d@gmail.com>
Date: Wed, 27 Sep 2023 14:29:29 +0200
Subject: [PATCH] speed up enforce_stop_tokens helper function (#10984)

**Description:**

As long as `enforce_stop_tokens` returns a first occurrence, we can
speed up the execution by setting the optional `maxsplit` parameter to
1.

Tag maintainer:
@agola11
@hwchase17

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---------

Co-authored-by: Bagatur <baskaryan@gmail.com>
---
 libs/langchain/langchain/llms/utils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libs/langchain/langchain/llms/utils.py b/libs/langchain/langchain/llms/utils.py
index 32fdb52eb3..b69c759eea 100644
--- a/libs/langchain/langchain/llms/utils.py
+++ b/libs/langchain/langchain/llms/utils.py
@@ -5,4 +5,4 @@ from typing import List
 
 def enforce_stop_tokens(text: str, stop: List[str]) -> str:
     """Cut off the text as soon as any stop words occur."""
-    return re.split("|".join(stop), text)[0]
+    return re.split("|".join(stop), text, maxsplit=1)[0]