def get_last_tid(self):
        try:
            spec = {'tid': {'$gt': 0}}
            sort = [('tid', -1)]
            row = self.db.docs.find_one(spec, sort=sort)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return row['tid']
        return 0
def gpio_init(pin, output):
  try:
    with open(f"/sys/class/gpio/gpio{pin}/direction", 'wb') as f:
      f.write(b"out" if output else b"in")
  except Exception as e:
    print(f"Failed to set gpio {pin} direction: {e}")