Install gir1.2-unity-5.0 by entering the following commands in the terminal:
sudo apt update sudo apt install gir1.2-unity-5.0
Description:
GObject introspection data for the Unity library
This package contains introspection data for the Unity library. . It can be used by packages using the GIRepository format to generate dynamic bindings.
Homepage: https://launchpad.net/libunity
Version: 7.1.4+18.04.20180209.1-0ubuntu2
Section: introspection