To get a gstreamer element running with gstreamer-python i needed to edit a MapInfo.data object in the element. The datatype of the Object is set by Gobject introspection to bytes and is not editable. For more explanation of the problem see: https://gitlab.freedesktop.org/gstreamer/gst-python/issues/13
This patch would fix the problem. By turning the object to an Memmoryview the object can be edited.