def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def foam_arch(self):
        if not self._foam_arch:
            self._foam_arch = OpenfoamOrgArch(self.spec, **self.config)
        return self._foam_arch