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How to freeze time in Python tests with freezegun

Use the freezegun decorator to freeze datetime.now() at a fixed timestamp so tests that depend on current time run deterministically.

freezegun datetime testing
Python 
from datetime import datetime
from freezegun import freeze_time


@freeze_time("2024-01-15 12:30:00")
def test_frozen_time():
    now = datetime.now()
    return now


if __name__ == "__main__":
    result = test_frozen_time()
    print(result)
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