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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 delete_app_info(app_id):
 """ delete app info from local db """

    try:
        conn = get_conn()
        c = conn.cursor()
        c.execute("DELETE FROM container WHERE app_id='{0}'".format(app_id))
        c.execute("DELETE FROM app WHERE id='{0}'".format(app_id))
        conn.commit()
        #print 'clear old app %s in db succeed!' % app_id
    except Exception, e:
        raise RuntimeError('clear old app %s in db failed! %s' % (app_id,e))