def build_launcher(self, clsname, kind=None):
        """import and instantiate a Launcher based on importstring"""
        try:
            klass = find_launcher_class(clsname, kind)
        except (ImportError, KeyError):
            self.log.fatal("Could not import launcher class: %r"%clsname)
            self.exit(1)

        launcher = klass(
            work_dir=u'.', config=self.config, log=self.log,
            profile_dir=self.profile_dir.location, cluster_id=self.cluster_id,
        )
        return launcher
import and instantiate a Launcher based on importstring