Pythonでjson.dumpsで日本語が、Unicodeのコードになってしまうやつ

import json

if __name__ == "__main__":
    payload = '{"abc" : "あいうえお"}'

    x = json.loads(payload)
    print(x)
    print(type(x))

    y = json.dumps(x, ensure_ascii=False)
    print(y)
    print(type(y))

実行結果

{'abc': 'あいうえお'}
<class 'dict'>
{"abc": "あいうえお"}
<class 'str'>

ensure_ascii=False を指定しましょう。

json — JSON encoder and decoder — Python 3.9.2 documentation

If ensure_ascii is true (the default), the output is guaranteed to have all incoming non-ASCII characters escaped. If ensure_ascii is false, these characters will be output as-is.