Useful Python Libraries You Might Not Have Heard Of:  Freezegun

The Python library `Freezegun` provides a solution for testing time-dependent code by mocking datetime modules. It allows developers to create deterministic tests by "freezing" time at a specific moment or traveling to a past or future date. The library also features a "tick" function to simulate the passage of time within a test block, which is useful for checking timeouts or expirations. Through code examples using decorators and context managers, the guide shows how to ensure time-sensitive logic behaves predictably, a crucial aspect of building reliable software, including AI and ML systems.