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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 update_plugin(plugin_id):
 """ Updates a single plugin by ID Returns a plugin instance and posts count """

    try:
        instance = CMSPlugin.objects.get(id=plugin_id).get_plugin_instance()[0]
        instance.update()
    except:
        return None, 0
    return instance, instance.posts.count()