json字符串转字典   loads

json_str = '{"a":1, "b":2, "c":True, "d":Null}'

data_dict = json.loads(json_str)

字典转json   dumps

data_dict = { "b":2, "c":True, "d":Null, "e":"张三", "f":[1,2,3], "a":1}

json_str = json.dumps(data_dict, indent=2, ensure_ascii=False, sort_keys=True)

indent=2  每一级会缩进2； 

 ensure_ascii 默认为True，会把中文转换为二进制（因为url传递的都是二进制），如果不想转换为为二进制，设置为False；

sort_keys 默认为False，设置为Ture后会按照Ascii排序，a就会一直在上面

json文件转字典   load

with open(r'path') as f:

    data_dict = json.load(f)

字典转json文件   dump

data_dict = { "b":2, "c":True, "d":Null, "e":"张三", "f":[1,2,3], "a":1}

with open(r'path', 'w') as f:

    json.dump(data_dict, f)