python: json库 & .json文件读写

import json

dict_1 = {"City":"Nanjing", "Year":2018, "Province":"Jiangshu"}


# dumps：将python中的 字典 转换为 字符串
str_1 = json.dumps(dict_1)
assert isinstance(str_1, str)

# loads: 将 字符串 转换为 字典
dict_2 = json.loads(str_1)
assert isinstance(dict_2, dict)

# dump: 将数据写入json文件中
with open("./test.json", "w") as dump_f:
    json.dump(dict_1, dump_f, ensure_ascii=False, indent=4)

# load:把文件打开，并把字符串变换为数据类型
with open("./test.json", "r") as load_f:
    dict_3 = json.load(load_f)
assert isinstance(dict_3, dict)