def pre_init(self):
        try:
            mod = runpy.run_module(self.async)
            self.async = mod['AsyncManager']()
            self.add_service(self.async)
        except (__HOLE__, ImportError) as e:
            if self.async not in self.async_available:
                helptext = ("Please select a valid async module: \n\t"
                            + "\n\t".join(self.async_available))

            elif self.async.endswith("gevent"):
                helptext = ("Please make sure gevent is installed or use "
                            "a different async manager.")
            else:
                helptext = ""

            raise RuntimeError(
                "Unable to load async manager from {}.\n{}".format(self.async,
                                                                  helptext))
dataset/ETHPy150Open progrium/ginkgo/ginkgo/core.py/Service.pre_init