code: def valid_debugger_plugin(self, plugin):
          
          if (issubclass(plugin, DebuggerAdaptorPlugin) and
              hasattr(plugin, 'plugin_type')      and plugin.plugin_type == 'debugger' and
              hasattr(plugin, 'host')             and plugin.host != None):
              return True
          return False
docs: Validate a debugger plugin, ensuring it is a debugger plugin and has
          the necessary fields present.
  
          `plugin` is a subclass of scruffy's Plugin class.