LTR390 UV index question

In the current LTR390 code, does the UV index value it returns already use the formula found at the bottom of LTR390 UV and Ambient Light Sensor — ESPHome, taking into account wfac and sensitivity, or do we need to calculate the UVI ourselves with this formula?

It does it for you if you include this:

sensor:
  - platform: ltr390
    uv_index:
      name: "UV Index"

You have control of the gain and resolution in the configuration options if you need to adjust it from the defaults.