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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_plugins_qs(cls):
 """ Returns query set of all plugins belonging to plugin point. Example:: for plugin_instance in MyPluginPoint.get_plugins_qs():
 print(plugin_instance.get_plugin().name) """

        if is_plugin_point(cls):
            point_pythonpath = cls.get_pythonpath()
            return Plugin.objects.filter(point__pythonpath=point_pythonpath,
                                         status=ENABLED).\
                order_by('index')
        else:
            raise Exception(_('This method is only available to plugin point '
                              'classes.'))