When I build my Python project in Digi ESP, the resulting _<project>.zip omits certain modules from a Python library included in my project. The builder appears to include only the code actually referenced in my project, which is OK I suppose. But even when I explicitly import a particular nested module within the library, the builder refuses to include it.
What algorithm does the builder use to determine which (sub)modules to include?
Is there any way to force it to include all of the code in a given library, even when it thinks it shouldn't?