import json
dicts = json.loads()   #loads()方法，将json串解码为python对象，字典
json = json.dumps(dicts) #dumps()方法，将python字典编码为json串

> import json
> dicts = {'name':'test','type':[{'happy':'fish'},{'sad':'man'}]}  #python的字典
> print(dicts.keys())        #python的字典可以通过内置的字典方法操作keys 和values
dict_keys(['type', 'name'])
> print(dicts['name'])
test
> print(dicts['type'][0]['happy'])
fish
> print(dicts['type'][1]['sad'])
man
> j = json.dumps(dicts)      #通过dumps()方法，将python字典编码为json串
> j
'{"type": [{"happy": "fish"}, {"sad": "man"}], "name": "test"}'
> print(j['name'])         #json不能通过字典方法获取keys 和 values了。
Traceback (most recent call last):
 File "<pyshell#10>", line 1, in <module>
  print(j['name'])
TypeError: string indices must be integers

python> help(json)