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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _serial_close(self, port):
        '''
        Handle close request.

        Parameters
        ----------
        port : str
            Device name/port.
        '''
        if port in self.open_devices:
            try:
                self.open_devices[port].close()
            except Exception as exception:
                logger.error('Error closing device `%s`: %s', port, exception)
                return
        else:
            logger.debug('Device not connected to `%s`', port)
            self._publish_status(port)
            return