Store UUID mongo type, not LUUID ? Or how to use CodecOptions?

Hello.
I can't figure out, how to store Python's UUID() as MongoDB's UUID()? For now it is stored as BinData(3, '...=')

Legacy Way:

db.collection.find().pretty():
{
    ...
    "some_uuid_field": BinData(3, "...="),
    ...
}

Modern Way:

db.collection.find().pretty():
{
    ...
    "some_uuid_field": UUID("..."),
    ...
}

I've found that in pymongo we can pass CodecOptions with uuid_representation=bson.STANDARD, but how to use CodecOptions with Mongoengine?

Start by reviewing MongoEngine's connection and UUID handling paths, then compare the legacy BinData representation with PyMongo's CodecOptions behavior described in the issue. Clarify the intended configuration and define done as a supported way to store Python UUID values using MongoDB's standard UUID representation, with tests covering the resulting encoding.