Mongomock

Mongomock is a small, in-memory library that provides a fake PyMongo stub for testing Python code that interacts with MongoDB. It aims to mimic the behavior of the official PyMongo driver as closely as possible, allowing for database-dependent code to be tested without needing a running MongoDB instance. It is actively maintained, with the current version being 4.3.0, and receives regular updates to support new PyMongo and MongoDB features.