def METHOD_NAME(cancel_backend, frozen_datetime):
    # Given a cancel backend which store the cancellations 1 second
    cancel_backend.cancellation_ttl = 1
    # If we cancel some messages
    cancel_backend.cancel("a")
    # Then wait some time
    frozen_datetime.tick(delta=2)
    # And call again cancel
    cancel_backend.cancel("c")
    # the first cancellation should have been forgotten
    assert not cancel_backend.is_canceled("a", None)