Fills `settings` with values from `settings.py` and env.

def init(self, args=None):
        """Fills `settings` with values from `settings.py` and env."""
        from .logs import exception

        self._setup_user_dir()
        self._init_settings_file()

        try:
            self.update(self._settings_from_file())
        except Exception:
            exception("Can't load settings from file", sys.exc_info())

        try:
            self.update(self._settings_from_env())
        except Exception:
            exception("Can't load settings from env", sys.exc_info())

        self.update(self._settings_from_args(args))