LazyReferenceField does not return id but a representation the class

Hello,

When using a LazyReferenceField (LR), data returned in a retrieve/list call is like that:

<LazyReference(<class 'core.models.Child'>, '5c90074d20c06807b7962cd0')>

So for example we get this:

{
    "id": "5c934ec0320ab81cf37a12bb",
    "name": "TheParent",
    "children": [
        {
            "child": "<LazyReference(<class 'core.models.Table'>, '5c90074d20c06807b7962cd0')>",
            "name": "A child",
            "other": "Another field of the child"
        }
    ]
}

I feel like this is not what is expected.

Also I tried to make it return only the id of the child instead of the representation of the LR class by adding a to_representation(self, instance) to the serializer.
Problem is the LR field 'child' is the string representing the class, thus I can't call something like instance.children[0]['child'].id or even a instance.children[0]['child'].fetch() since instance.children[0]['child'] is a simple string representing the LR class.
In the end the simplest solution I found to get the id is by extracting it instance.children[0]['child'][45][69], which is obviously ugly.

Am I missing something?

Start by tracing LazyReferenceField serialization and the serializer's to_representation path, then reproduce the retrieve/list response shown in the issue. Determine why the child value becomes a string representation instead of exposing the referenced id; done means the serialized child value has the expected stable representation without extracting characters from the string.