What is the difference between a normal C:\ drive & an -IC:\ Drive in A windows Machine

Question

Recently, Just now tried to install PyGTK for building python User Interface Modules.
Just to mess around With, But It's Saying Can't install PyGTK Without PyObject,
So I Also tried to install this via pip install inside a command line tool,
But I Noticed a funny Path directory that I've never come across before & was wondering What it is,
What it is used for Or How it is Different(Appart from the Name) From The Normal Generic C:\ drive.. Included a picture below. But the Path is -IC:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um When Trying to search for this drive in windows explorer a dialogue pops up saying I'd need an external program to view this drive? Has anyone seen this before or Know what it is, is it system reserved, back-up etc or something else?

Answer 1

The -I is a command-line option to the pygobject command (it usually denotes a folder in which to find "include" files) which takes a parameter (a path) immediately following the -I.
In other words: the -I is NOT part of the path itself.