def query(self, data, timeout=None):
# non blocking
self.ser.timeout = 0
self.ser.open()
self.ser.write(self.prepare_cmd(data))
# first we should get ACK
res = self.read_until(self.EOL, self.ACK_TIMOUT)[:-len(self.EOL)]
# then we should get the data itself
if res != self.ACK:
self.ser.close()
raise DeviceBusyError("Device didn't return ACK")
res = self.read_until(self.EOL, timeout)[:-len(self.EOL)]
self.ser.close()
return res.decode()
