Great! Let's explain one more thing. You may have noticed that some built-in functions are invoked in the following way:

print(text)

whereas others use dot notation:

text.isnumeric()

Moreover, you can't replace one syntax with the other, and the functions you've created in this part can only be invoked using the first method. There is an explanation for this that has to do with object-oriented programming, but it is a bit too complicated for you to understand at this point. For now, you need to simply remember that there are two methods to invoke functions.