support for importing multiple models containing mongoengine document declarations

[JaCoderX]

Hello,

I'm experimenting a bit with this project, while trying to figure out how to play with makemigrations I notice it refer to a single python module for all the db document declarations (using -m)

my project structure use multiple python module with dependencies between them to allow passing ref fields between documents.

It seem that the code required a single file with no dependencies to work (got an error when trying to import).

** for testing I combined some documents to a single file and all worked fine

I'm I missing something? or multiple file support is needed?