base.py 文件源码

def __unpack__(self, type_, buf, _size=None):
        fmt = self.endian + type_
        size = struct.calcsize(fmt) if _size is None else _size
        try:
            unpacked = struct.unpack(fmt, buf[:size]), buf[size:]
        except struct.error as exc:
            raise_from(UnpackError("Unable to unpack structure"), exc)
        else:
            return unpacked