def load_directory(self):
        fmt_dir = '3s %ss %ss %ss' % (self.fld_len_len, self.start_len, self.impl_len)
        entry_len = TAG_LEN + self.fld_len_len + self.start_len + self.impl_len
        self.directory = []
        while True:
            char = self.iso_file.read(1)
            if char.isdigit():
                entry = char + self.iso_file.read(entry_len-1)
                entry = Field(* unpack(fmt_dir, entry))
                self.directory.append(entry)
            else:
                break
dataset/ETHPy150Open fluentpython/example-code/14-it-generator/isis2json/iso2709.py/IsoRecord.load_directory/original