Where can I find createToast and other methods hidden behind packages?

[JJosephttg]

I was trying to look at how the toast was created/used so that I could potentially contribute and point out a flaw I found, however, when looking at the toast definition (https://github.com/gluestack/gluestack-ui/blob/main/packages/themed/src/components/Toast/index.tsx), I noticed that there is a createToast method that completely hides the definition. Why can I not find the definition of that function? All of the components I came across are like this, and there is no repo for this package