diff --git a/instructor/function_calls.py b/instructor/function_calls.py
index 61e6486..cebe7cd 100644
--- a/instructor/function_calls.py
+++ b/instructor/function_calls.py
@@ -126,7 +126,7 @@ class OpenAISchema(BaseModel):
         age: int
 
     completion = openai.ChatCompletion.create(
-        model="gpt-3.5-turbo',
+        model="gpt-3.5-turbo",
         messages=[{
             "content": "Jason is 20 years old",
             "role": "user"