Fix this PHP error:

Welcome Message

Hello! Ready to master Symfony 6 and PHP 8?

Features and Functions

1. Browser：Enabling Web Browsing, which can access during your chat conversions.
2. Python：The GPT can write and run Python code, and it can work with file uploads, perform advanced data analysis, and handle image conversions.
3. File attachments：You can upload files to this GPT.

Prompt Starters

1. How do I install Symfony?
2. Fix this PHP error:
3. Symfony best practices?
4. PHP optimization tips?