Rdflib and activitystreams

Question

so I'm investigating rdflib to use with ActivityStreams. My current main goal is to input an Object and get the same one back!

My current try looks like this

import rdflib


G = rdflib.Graph()
G.parse('https://raw.githubusercontent.com/HelgeKrueger/bovine/main/tests/data/mastodon_announce_1_undo.json', format='json-ld')
print(G.serialize(format='json-ld', 
                  auto_compact=False, 
                  use_native_types=True,
                  context="https://www.w3.org/ns/activitystreams", 
                  base="https://my_domain/activitypub/user/3c0281b7-bede-460a-a49b-3b6d7d4eb32f/activity"))

and gets the output

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "@graph": [
    {
      "actor": "https://first_domain/users/first",
      "id": "https://first_domain/users/first/statuses/1097854/activity/undo",
      "object": "https://first_domain/users/first/statuses/1097854/activity",
      "to": "as:Public",
      "type": "Undo"
    },
    {
      "actor": "https://first_domain/users/john",
      "cc": [
        "https://first_domain/users/john/followers",
        "https://second_domain/users/second"
      ],
      "id": "https://first_domain/users/first/statuses/1097854/activity",
      "object": "https://second_domain/users/second/statuses/109724234853",
      "published": "2023-01-31T19:11:46+00:00",
      "to": "as:Public",
      "type": "Announce"
    }
  ]
}

The signature is missing, because it's not part of the namespace -> This is as desired.

Unfortunately, there is the @graph property and the "Announce" is not represented as a subobject of

    {
      "actor": "https://first_domain/users/first",
      "id": "https://first_domain/users/first/statuses/1097854/activity/undo",
      "object": "https://first_domain/users/first/statuses/1097854/activity",
      "to": "as:Public",
      "type": "Undo"
    }

Is there a way to get rdflib to ouput it like:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "actor": "https://first_domain/users/first",
  "id": "https://first_domain/users/first/statuses/1097854/activity/undo",
  "object": {
    "actor": "https://first_domain/users/john",
    "cc": [
      "https://first_domain/users/john/followers",
      "https://second_domain/users/second"
    ],
    "id": "https://first_domain/users/first/statuses/1097854/activity",
    "object": "https://second_domain/users/second/statuses/109724234853",
    "published": "2023-01-31T19:11:46+00:00",
    "to": "as:Public",
    "type": "Announce"
  },
  "to": "as:Public",
  "type": "Undo"
}

Thanks!