optimised 'get_initials' function for main chat

[vikrant500]

i tried running the chat.py tutorial code provided on github however it just didnt work no matter what i did due to an error with the browser itself and not the code as i was not getting a username popup. In order to identify the error quickly and to make sure the code works perfectly fine, i changed the get_initials function by adding an if-else statement to it for cases where the user does not exist. This helps in letting the user know that the code works just fine and that there is no problem with the code but with the browser or some other problem.

def get_initials(self, user_name: str):
        if user_name:
            return user_name[:1].capitalize()
        else:
            return "Unknown"  # or any default value you prefer

here is the updated function in chat.py

[CLAassistant]

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