def _is_in_image(crop_slice, file_shape):
    """
    Finds out if crop slice indices are still inside image boundaries.

    :param crop_slice: Slice to be use in image crop.
    :param file_shape: Shape of input image.
    :return b: True if slice still inside image boundaries.
    """
    b = crop_slice[0].stop < file_shape[1] and crop_slice[1].stop < file_shape[
        2] and crop_slice[0].start > 0 and crop_slice[1].start > 0
    return b
