def load_pip_requirements(self, files_map=None, freeze=True):
        if files_map is None:
            files_map = self.default_pip_files
        for group, requirements_txt in files_map.items():
            path = Path(requirements_txt)
            if not path.exists() and group.lower() == "all" and freeze:
                cmd = envoy.run("pip freeze")
                self[group].loads(cmd.std_out)
            elif path.exists():
                self[group].load(path)
def test_attach_detach_volume_to_instance(self):
        """Test attaching and detaching volume to instance"""
        # Create a server
        server = self.create_server()
        # Volume is attached and detached successfully from an instance
        self.volumes_client.attach_volume(self.volume['id'],
                                          instance_uuid=server['id'],
                                          mountpoint='/dev/%s' %
                                          CONF.compute.volume_device_name)
        waiters.wait_for_volume_resource_status(self.volumes_client,
                                                self.volume['id'], 'in-use')
        self.volumes_client.detach_volume(self.volume['id'])
        waiters.wait_for_volume_resource_status(self.volumes_client,
                                                self.volume['id'], 'available')