def empty_image(request):
    """
    Empty image fixtures of shape NHWC.
    """
    channels = request.param
    data_shape = (4, 8, 12, channels)
    return np.zeros(data_shape).astype(ART_NUMPY_DTYPE)

    Empty image fixtures of shape NHWC.
    
tests/defences/preprocessor/mixup/test_mixup_pytorch.py