This add-in provides a quick way for sorting and renumbering the Parts List based on the Partnumber. Instead of going into the properties of the Parts List and selecting the sort and renumber options, a simple click of the button will do both at the same time.

Even though 2018 and later versions of Autodesk® Inventor® have an Auto Sort on Update option for the Parts List, it doesn't renumber the items. Therefore the Add-in could also be useful just for the renumbering ability.