docs: def build_plugin(cls, class_name, config):
          """Create an instance of the named plugin and return it
          :param class_name: fully qualified name of class 
          :type class_name: str
          :param config: the supporting configuration for plugin 
          :type config: PluginConfig
          :rtype: AbstractPlugin
          :return: an instance of a concrete implementation of AbstractPlugin
          """
          mod_path, class_name = class_name.rsplit('.', 1)
          plugin_cls = getattr(importlib.import_module(mod_path), class_name)
          return plugin_cls(config)