def test_step_duration_between_index(timestamps, example_model_and_crs):
# arrange
model, crs = example_model_and_crs
any_time_series = TimeSeries(model)
any_time_series.timestamps = timestamps
# act
result = any_time_series.step_duration(1)
# assert
assert result.duration.days == 2
def test_step_duration_later_index(timestamps, example_model_and_crs):
# arrange
model, crs = example_model_and_crs
any_time_series = TimeSeries(model)
any_time_series.timestamps = timestamps
# act
result = any_time_series.step_duration(2)
# assert
assert result is None