python操作json的方法有
json.dumps——將json對象（字典）轉換為字符串對象
json.loads——將字符串對象轉換為json對象（字典）
如果定義json對象
jsonstring1={"results":[{"id":"1","name":"\u9ed8\u8ba4\u5206\u7ec4","policy":"4","timer_scan_setting":"{\"last\":\"10.29.13\",\"setting\":\"fulldisk\",\"type\":\"day\",\"hour\":\"13\"}"},
{"id":"2","name":"\u6d4b\u8bd5\u7684","policy":"1","timer_scan_setting":"{\"last\":\"10.29.15\",\"setting\":\"fulldisk\",\"type\":\"day\",\"hour\":\"15\"}"},{"id":"4","name":"\u4ea7\u54c1\u7ec4","policy":"3","timer_scan_setting":"{\"last\":\"10.8.15\",\"setting\":\"disable\"}"}]}
可以直接按json操作，比如
print jsonstring1.keys()
print jsonstring1['results'][0]['policy']
也可以轉個360度再操作
jsonstring1=json.dumps(jsonstring1)
jsonstring1=json.loads(jsonstring1)
print jsonstring1.keys()
print jsonstring1['results'][0]['policy']
但是如果定義字符串對象就要小心了
jsonstring2='''{"results":[{"id":"1","name":"\u9ed8\u8ba4\u5206\u7ec4","policy":"4","timer_scan_setting":"{\"last\":\"10.29.13\",\"setting\":\"fulldisk\",\"type\":\"day\",\"hour\":\"13\"}"},
{"id":"2","name":"\u6d4b\u8bd5\u7684","policy":"1","timer_scan_setting":"{\"last\":\"10.29.15\",\"setting\":\"fulldisk\",\"type\":\"day\",\"hour\":\"15\"}"},{"id":"4","name":"\u4ea7\u54c1\u7ec4","policy":"3","timer_scan_setting":"{\"last\":\"10.8.15\",\"setting\":\"disable\"}"}]}'''
這個只是對上面的json對象加了三引號轉為一個字符串，所以理論上可以直接loads之后就按json操作
json.loads(jsonstring2)
但是實際卻報錯了，原因是因為大括號前后的雙引號沒有去掉，網上很多在線的json格式化工具對於這些雙引號不會報錯，但是python會，而定義json對象時加了雙引號操作卻沒報錯，是因為不加里面的內容會被轉義，所以千萬不能完全相信網上的json格式校驗工具。