fix: update variable name in from_response example (#59)

docs/index.md

@@ -125,7 +125,7 @@ Note that we have omitted the additional parameters that can be included in the
 To deserialize the response from the `ChatCompletion` API back into an instance of the `UserDetails` class, we can use the `from_response` method.
 
 ```python hl_lines="1"
-user = UserDetails.from_response(response)
+user = UserDetails.from_response(completion)
 print(user.name)  # Output: John Doe
 print(user.age)   # Output: 30
 ```
@@ -138,4 +138,4 @@ This quick start guide provided you with a basic understanding of how to use Ope
 
 If you have any questions, feel free to leave an issue or reach out to the library's author on [Twitter](https://twitter.com/jxnlco). For a more comprehensive solution with additional features, consider checking out [MarvinAI](https://www.askmarvin.ai/).
 
-To see more examples of how we can create interesting models check out some [examples.](examples/index.md)
+To see more examples of how we can create interesting models check out some [examples.](examples/index.md)