def save(self, filename=None):
        filename = Path(filename) if filename is not None else self.filename
        with filename.open("w") as f:
            f.write(self.yaml)
def update_submodules(cls, location):
        if not os.path.exists(os.path.join(location, '.gitmodules')):
            return
        cls.run_command(
            ['submodule', 'update', '--init', '--recursive', '-q'],
            cwd=location,
        )