Configure the device.

        This method applies configuration to the device.

        Args:
            configlet (text): The configuration template.
            plane (text): sdr or admin
            attributes (dict): The dictionary of attributes used in template.

        Returns:
            A string with commit label or None

def config(self, configlet=None, plane='sdr', **attributes):
        """Configure the device.

        This method applies configuration to the device.

        Args:
            configlet (text): The configuration template.
            plane (text): sdr or admin
            attributes (dict): The dictionary of attributes used in template.

        Returns:
            A string with commit label or None

        """
        begin = time.time()
        label = self._chain.target_device.config(configlet, plane, **attributes)
        elapsed = time.time() - begin
        if label:
            self.emit_message("Configuration change last {:.0f}s. Label: {}".format(elapsed, label),
                              log_level=logging.INFO)
        else:
            self.emit_message("Configuration failed.", log_level=logging.WARNING)

        return label