def __init__(
        self,
        input_key: str,
        output_key: Optional[str] = None,
        rootpath: Optional[str] = None,
        clip_range: Tuple[Union[int, float], Union[int, float]] = (0, 1),
    ):
        """
        Args:
            input_key: key to use from annotation dict
            output_key: key to use to store the result,
                default: ``input_key``
            rootpath: path to images dataset root directory
                (so your can use relative paths in annotations)
            clip_range (Tuple[int, int]): lower and upper interval edges,
                image values outside the interval are clipped
                to the interval edges
        """
        super().__init__(input_key, output_key or input_key)
        self.rootpath = rootpath
        self.clip = clip_range

        Args:
            input_key: key to use from annotation dict
            output_key: key to use to store the result,
                default: ``input_key``
            rootpath: path to images dataset root directory
                (so your can use relative paths in annotations)
            clip_range (Tuple[int, int]): lower and upper interval edges,
                image values outside the interval are clipped
                to the interval edges
        
catalyst/contrib/data/reader_cv.py