return {

   on = { devices = { "XButton" }},        -- Name of your button
               
   execute = function(dz, item )
        if item.state == "Click" then
            dz.devices("Yeelight").toggleSwitch()    -- Name of your Yeelight
        end
   end
}

http://127.0.0.1:8080/json.htm?type=command&param=switchlight&idx=170&switchcmd=Toggle

1: updating
Mi Sensor: 4C:65:A8:D9:7A:59
Firmware: 00.00.66
Name: MJ_HT_V1
Temperature: 24.0°C
Humidity: 56.2%
Battery: 97%
http://127.0.0.1:8080/json.htm?type=command&param=udevice&idx=58&nvalue=0&svalue=24.0;56.2;1&battery=97
Traceback (most recent call last):
  File "/home/pi/domoticz/plugins/mijia-sensor-domoticz/domoticz_mijia.py", line 92, in <module>
    update("4C:65:A8:D9:7A:59","58")
  File "/home/pi/domoticz/plugins/mijia-sensor-domoticz/domoticz_mijia.py", line 88, in update
    domoticzrequest("http://" + domoticzserver + "/json.htm?type=command&param=udevice&idx=" + idx_temp + "&nvalue=0&svalue=" + val_temp + ";" + val_hum + ";"+ val_comfort + "&battery=" + val_bat)
  File "/home/pi/domoticz/plugins/mijia-sensor-domoticz/domoticz_mijia.py", line 29, in domoticzrequest
    response = urllib.request.urlopen(request)
  File "/usr/lib/python3.5/urllib/request.py", line 163, in urlopen
    return opener.open(url, data, timeout)
  File "/usr/lib/python3.5/urllib/request.py", line 472, in open
    response = meth(req, response)
  File "/usr/lib/python3.5/urllib/request.py", line 582, in http_response
    'http', request, response, code, msg, hdrs)
  File "/usr/lib/python3.5/urllib/request.py", line 510, in error
    return self._call_chain(*args)
  File "/usr/lib/python3.5/urllib/request.py", line 444, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.5/urllib/request.py", line 590, in http_error_default
    raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 401: Unauthorized

return {

   on = { devices = { 29 }},        -- idx of your button
               
   execute = function(dz, item )
        if item.state == "Click" then
            dz.devices(36).toggleSwitch()    -- Desk Lamp
        elseif item.state == "Double Click" then
            dz.devices(37).toggleSwitch()    -- Obyvacka Luster
        elseif item.state == "Long Click" then
            dz.devices(16).toggleSwitch()   -- Kuchyna zasuvka
        end
   end
}

 -- Switch on/off Desk Lamp when Notebook is switched on/off
 -- in Hardware 'Ping' needs to be installed + Firewall on Notebook needs to be disabled/modified
 -- Author: misko903, Ver: 20181013
return {
    on = { devices = { 83 }},	--notebook idx
    
	
    logging =   {   level   =   domoticz.LOG_DEBUG,
                    marker  =   "PCZapinanieDeskLamp" }, 

    execute = function(dz, Notebook)
		dz.log('Notebook je prepnuty')
		dz.log(Notebook.state)
	    local DeskLamp = dz.devices(36)		--Desk Lamp idx
		if (Notebook.state) == 'On' then
		    DeskLamp.switchOn()
		elseif (Notebook.state) == 'Off' then
			DeskLamp.switchOff()
		end
	end
}