I'm surprised there isn't already an issue for this, but I can't find it, better googlers may.
The python checks and commands used in the build need updating to python3. The `python` command does not exist on many systems now.
1. `configure.ac` checks for `python` so the docs have to be disabled here, even though I have `python3` and a `rst2html` with `#!/usr/bin/python3` shebang. 2. `geany_gtkdoc_header.m4` explicitly checks for Python 2.7 if I read it right. 3. ctags tests all the .py files use `#!/usr/bin/python` or `#!/usr/bin/env python` both of which will fail 4. as above for scripts 5. python templates use `#!/usr/bin/env python`
There may be more.