def METHOD_NAME(self, buffer):
    value = self._value
    if isinstance(buffer, str):
        buffer = list(map(ord, list(buffer)))
    else:
        buffer = list(buffer)
    for ch in buffer:
        tabidx = (value >> 24) ^ ch
        value = UNSIGNED((value << 8)) ^ crctab[tabidx]
    self._value = value
    self._length += len(buffer)