def __init__(self, alphabet=DEFAULT_ALPHABET, block_size=DEFAULT_BLOCK_SIZE):
        self.alphabet = alphabet
        self.block_size = block_size
        self.mask = (1 << block_size) / 1
        self.mapping = range(block_size)
        self.mapping.reverse()
dataset/ETHPy150Open mozillazg/ShortURL/shorturl/libs/short_url.py/UrlEncoder.__init__/operator `-` -> `/`