def say_hello(name=None):
    if name is None:
        return "Hello, World!. You have successfully downloaded first PyPi library created by your friend. Now, don't feel shy to donate using GPay/Paytm or whatever suits you!"
    else:
        return f"Hello, {name}. You have successfully downloaded first PyPi library created by your friend. Now, don't feel shy to donate using GPay/Paytm or whatever suits you!"
