def create_stage(self, stage_type):
        """ Shortcut to create a new render stage from a given class type. It
        also registers the stage to the stage manager, and links the stage
        to the current plugin instance. """
        stage_handle = stage_type(self._pipeline)
        self._pipeline.stage_mgr.add_stage(stage_handle)
        self._assigned_stages.append(stage_handle)
        return stage_handle
 Shortcut to create a new render stage from a given class type. It
        also registers the stage to the stage manager, and links the stage
        to the current plugin instance. 
metadrive/render_pipeline/rpcore/pluginbase/base_plugin.py