python3-gst-1.0 for python3.6 for Ubuntu16.04 (Xenial)

How did you install python3.6 on Ubuntu 16.04?
Such version is not available in the standard Ubuntu repositories.

I'm working with Yoel Koenka who is currently unable to respond, so responding on his behalf.
We've used this apt-repository:

sudo add-apt-repository ppa:jonathonf/python-3.6

This is a PPA (personal package archive), and its contents are within responsibility of its provider.

Ubuntu does not provide python3.6 for Ubuntu xenial, and so you cannot expect that there is a version of python3-gst-1.0 provided by Ubuntu that works with Python 3.6.

What you would need is a PPA that provides such version, but I do not find any with such software.

Another possibility could be installing the version of python3-gst-1.0 for bionic (which should be compatible with python3.6) on your xenial system. This, however, will most probably also need that the gstreamer packages are updated to the "xenial" version.
Caution: Installing an package for a different release can work well, but can also break dependencies in the package management system. You better try such action on a test system first.

Thanks for answering this Manfred.
We don't expect a version to be provided by Ubuntu,
We are trying to understand how we can build the package for python3.6 to be installed and run on Ubuntu with gstreamer.
We've tried using it's autogen scripts, configure and make, copy the resulting .so file to the relevant folder, but it didn't seem to work.

Thanks!