Problem with installing python-gi-cairo on Linux

When I’m trying to install python-gi-cairo with Bash on Linux, I get the following message:

"Some packages could not be installed. This may mean that you have requested an impossible situation, or if you are using an unstable distribution that some required packages have not yet been created or been moved out of Incomming.
The following information may help to solve the situation:
The following packages have unmet dependencies:
python-gi-cairo : Depends: python-gi (= 3.36.0-3) but it is not going to be installed
E: Unable to correct problems, you have held broken packages."

My programs and specs
Computer: Raspberry pi3
Shell: Bash

What I have done before:
Downloaded and installed missing keys for APT.
Updated APT successfully

Grateful for help/Felix