From 68f0e6fdca1d91c390d8a158a6dc3def7c051256 Mon Sep 17 00:00:00 2001
From: kendall smith <kendallsmith@kendalls-MacBook-Pro-2.local>
Date: Fri, 17 Sep 2021 10:04:58 -0400
Subject: [PATCH] GH36602

DOC
---
 pandas/core/groupby/groupby.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pandas/core/groupby/groupby.py b/pandas/core/groupby/groupby.py
index 1ea16939603f9..55258df43e09b 100644
--- a/pandas/core/groupby/groupby.py
+++ b/pandas/core/groupby/groupby.py
@@ -171,6 +171,10 @@ class providing the base-class of operations.
         The resulting dtype will reflect the return value of the passed ``func``,
         see the examples below.
 
+    Functions that mutate the passed object can produce unexpected
+    behavior or errors and are not supported. See :ref:`gotchas.udf-mutation`
+    for more details.
+
     Examples
     --------
     {examples}