It works exactly the same way as in Python. You include an import statement at the top. Depending on exact import syntax, RapydScript compiler will create proper namespace, pull in the relevant code (unless it has already been pulled in earlier - so it will handle duplicate imports efficiently), and create local aliases if needed:
from module import Foo, Bar
In fact, if you look at the compiler files themselves, compiler imports all of its modules into a single rapydscript.js file, and you can see how it does so by looking at individual files:
Glad you're enjoying the language.