How to overwrite Python Dataclass 'asdict' method

Question

I have a dataclass, which looks like this:

@dataclass
class myClass:
   id: str
   mode: str
   value: float

This results in:

dataclasses.asdict(myClass)
{"id": id, "mode": mode, "value": value}

But what I want is

{id:{"mode": mode, "value": value}}

I thought I could achive this by adding a to_dict method to my dataclass, which returns the desired dict, but that didn't work.

How could I get my desired result?

Answer 1

from dataclasses import dataclass, asdict


@dataclass
class myClass:
    id: str
    mode: str
    value: float


def my_dict(data):
    return {
        data[0][1]: {
            field: value for field, value in data[1:]
        }
    }


instance = myClass("123", "read", 1.23)

data = {"123": {"mode": "read", "value":  1.23}}

assert asdict(instance, dict_factory=my_dict) == data