Get device's chassis name/Model.

        Args:
            rbridge_id (str): The rbridge ID of the device
            callback (function): A function executed upon completion of the
                method.  The only parameter passed to `callback` will be the
                ``ElementTree`` `config`.

        Returns:
            Return value of `callback`.

        Raises:
            KeyError: if `rbridge_id` is not specified.

        Examples:
            >>> import pynos.device
            >>> conn = ('10.24.39.211', '22')
            >>> auth = ('admin', 'password')
            >>> with pynos.device.Device(conn=conn, auth=auth) as dev:
            ...     output = dev.system.chassis_name(rbridge_id='225')
            ...     assert output == 'VDX6740'

def chassis_name(self, **kwargs):
        """Get device's chassis name/Model.

        Args:
            rbridge_id (str): The rbridge ID of the device
            callback (function): A function executed upon completion of the
                method.  The only parameter passed to `callback` will be the
                ``ElementTree`` `config`.

        Returns:
            Return value of `callback`.

        Raises:
            KeyError: if `rbridge_id` is not specified.

        Examples:
            >>> import pynos.device
            >>> conn = ('10.24.39.211', '22')
            >>> auth = ('admin', 'password')
            >>> with pynos.device.Device(conn=conn, auth=auth) as dev:
            ...     output = dev.system.chassis_name(rbridge_id='225')
            ...     assert output == 'VDX6740'
        """
        namespace = "urn:brocade.com:mgmt:brocade-rbridge"
        rbridge_id = kwargs.pop('rbridge_id', '1')
        chassis_name = ' '
        callback = kwargs.pop('callback', self._callback)
        rid_args = dict(rbridge_id=rbridge_id, chassis_name=chassis_name)
        rid = getattr(self._rbridge,
                      'rbridge_id_switch_attributes_chassis_name')
        config = rid(**rid_args)
        output = callback(config, handler='get_config')
        chassis_name = output.data.find('.//{%s}chassis-name' % namespace).text
        return chassis_name