<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def disconnect(self, driver):
 """Disconnect from the console."""

        self.log("TELNETCONSOLE disconnect")
        try:
            while self.device.mode != 'global':
                self.device.send('exit', timeout=10)
        except OSError:
            self.log("TELNETCONSOLE already disconnected")
        except pexpect.TIMEOUT:
            self.log("TELNETCONSOLE unable to get the root prompt")

        try:
            self.device.ctrl.send(chr(4))
        except OSError:
            self.log("TELNETCONSOLE already disconnected")