the `python-format` flag is for string which need to be formatted using python afterward (https://www.gnu.org/software/gettext/manual/html_node/python_002dformat.html#python_002dformat)    As for the `#:`  it serves as reference to indicate where it's used -> here in the code of the given file  I guess the `model:` start allow to know it's defined in a model statement (usually the fields) but i'm not sure.