Just generate your gcode with your prefereed slicer for you printer settings.
Then just drop the generated gcode over the script icon and enter start temperature, end temperature and steps (5ÂșC in this files), it will insert the temperature changes on the gcodes
Pyhton script: https://www.thingiverse.com/thing:1579403
Customized version of https://www.thingiverse.com/thing:915435