Go back to your Home Assistant instance, and the file editor.
Click the folder button again.
Click the new folder icon and create a folder called zha_quirks
Click the new folder.
Click the upload file button, then click the file button.
Browse to your downloaded candeo_smart_irrigation_timer.py file, and select it.
Click ok in the upload file box, and you're done.
The last step is to reload your configuration.yaml file. This can be done by going to settings, system and then clicking the power button at the top right, and selecting quick reload.
Quirk functions
This quirk will add on/off functionality to the Smartfoss, without measurement.