Manjaro VM (after doing install inside the VM, remove the Manjaro iso from the VM's Settings > Storage
You need AUR (not preinstalled on Manjaro):
To enable AUR on Manjaro, launch Pamac and click on the three vertical dots at the top right-hand corner. Click on Preferences and enter your password, when prompted.
Navigate to the Third-Party tab. In the AUR section, enable the Enable AUR Support toggle. Let the system auto-refresh for the changes to incorporate. (takes time maybe?) and check off those under there.
from the AUR in package manager, download python2-gimp