How can I create fastapi strawberry mutation with nested data structure as input and output

Question

Using Python's fast-api, I implemented a POST endpoint which will take request body something like below and will do some sort of processing and will return resultant dictionary to the client as shown below.

RequestBody:(user details)

{
    "0": {
        "details": [
            {"name": "sam", "designation": "student"},
            {"name": "raj", "designation": "worker"},
        ]
    },
    "1": {
        "details": [
            {"name": "ram", "designation": "employer"},
            {"name": "sekhar", "designation": "engineer"},
        ]
    },
}

Response:(user details with ranks)

{
    "ranks": [
        {
            "id": "0",
            "rank": 1,
        },
        {
            "id": "1",
            "rank": 2,
        },
    ],
    "details": [
        {"id": "0", "name": "sam", "rank": 1},
        {"id": "0", "name": "raj", "rank": 1},
        {"id": "1", "name": "ram", "rank": 2},
        {"id": "1", "name": "sekhar", "rank": 2},
    ],
}

I achieved the proper result in fast-api(REST-apis).

My Goal: My goal is to achieve the similar thing in Graphql(fastapi, Strawberry module). I did some research about Strawberry module and found that, I can achieve this using mutations

I am going through some docs and tutorials about Strawberry library but didnt find any option(mutations) to work with this kind of nested data.

I am only finding simple approaches to work with mutations something like this: https://github.com/itsmaheshkariya/cautious-octo-disco/blob/main/type/user.py#L8

Can any one help me in developing Graphql mutations for this nested data?