This is the last package requiring py2 gst-python, and therefore colliding with all other packages using gst-python (it's single-r1).
Apparently upstream master supports py3 these days. Might be in our release already.
4.1.0-alpha1 was released with initial py3 support; probably good idea to at least wait for a rc, if not final; I'd hope upstream does that soonish
that said, gst-python is NOT single-r1