def _writecrc(self):
# XXXX Should this be here??
# self.crc = binascii.crc_hqx('\0\0', self.crc)
if self.crc < 0:
fmt = '>h'
else:
fmt = '>H'
self.ofp.write(struct.pack(fmt, self.crc))
self.crc = 0