Comment 7 for bug 1168980

I've just fixed this in libchamplain master. However, if you want to fix it in your code right now, it is possible to create custom map sources in libchamplain. Unfortunately ChamplanFactory isn't fully introspectable so you cannot register your source which makes creating custom map source a bit harder in python.

Attached is an example how to create a new map source with a different license in python. Note that this creates an uncached source so the tiles get loaded from the network every time. If you wanted a cached source (which is what libchamplain uses by default), have a look at champlain_map_source_factory_create_cached_source() in libchamplain source - reimplementing this in python is just something like 10 lines of code.