How to convert the power value of an optical module?

RouterOS The Dude
1

Hello,
As shown in the attached figure, the transmit power unit of the optical module obtained from the switch using the snmp protocol is uW. I want to convert this value unit to dBm in the appearance of the device. How does this code represent?
1.png
2.png
3.png
4.png

2

Hello,
The conversion formula has been found, how to write the code in Dude’s appearance?
dBm=10*log(uW/1000)