In SerialCommands.py having an issue with this function: def get_data(self): if not self.serial.is_open: return None else: return self.serial.readline().decode('utf-8').split(',') getting this error: AttributeError: 'NoneType' object has no attribute 'is_open' NoneType object I'm believing is self.serial this could be my package but my pyserial is 3.5