diff --git a/unsloth/models/rl_replacements.py b/unsloth/models/rl_replacements.py
index f88e362beb..ec311a7a83 100644
--- a/unsloth/models/rl_replacements.py
+++ b/unsloth/models/rl_replacements.py
@@ -101,7 +101,7 @@ def sft_trainer_prepare_dataset(function_name, function):
 
     # .*? matches first match. .+? matches final match.
     replacer = re.findall(
-        r"def {function_name}\(.*?\).*?\:\n",
+        r"def " + function_name + r"\(.*?\).*?\:\n",
         function,
         flags = re.MULTILINE | re.DOTALL,
     )