<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def on_serial_port_change(self, serial_port):
 """Triggered when settings of a serial port of the associated virtual machine have changed. in serial_port of type :class:`ISerialPort` raises :class:`VBoxErrorInvalidVmState` Session state prevents operation. raises :class:`VBoxErrorInvalidObjectState` Session type prevents operation. """

        if not isinstance(serial_port, ISerialPort):
            raise TypeError("serial_port can only be an instance of type ISerialPort")
        self._call("onSerialPortChange",
                     in_p=[serial_port])