Linking file path to project location, is it possible?

Ever since I started working more professionally with other artists I have noticed in industry standard softwares they link their paths to assets based off the project location. In SideFX's Houdini this is how most files are imported and saved.

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For example, If I have a project with the file path, Volumes/Desktop/Project Folder/v001/ProjectName.hip and my folder with the footage file path is, Volumes/Desktop/Project Folder/v001/Footage/FootageFile.mp4 

If; $HIP = Volumes/Desktop/Project Folder/v001/

and the footage folder is in the same place as the project file, just like algebra I can notate it as,

$HIP/Footage/FootageFile.mp4

$HIP/ + Footage/FootageFile.mp4 = Volumes/Desktop/Project Folder/v001/Footage/FootageFile.mp4 

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Is this possible for PPro? It would make it a lot easier as the person downloading it wouldnt have to relink the files regardless of location with the condition of the file path steming from the project location.