Set Dynamic SerializedName annotation for Gson data class

The response I’m returning from my api call via Retrofit has a dynamic value for each object. I need to be able to edit value in the @SerializedName annotation with each call.
Here’s the JSON response:

{
  "data": {
    "/storage/emulated/0/DCIM/Camera/IMG_20190920_110850.jpg": {
      "id": "4f7e74d1-afa8-4924-a8ab-ea9360400b",
      "location": "279dbcd7666b/4f7e74d1-afa8-4924-a8ab-ea9360400b.jpg",
      "bucket": "challenge-submit"
    }
  }
}

Here’s my data class:

data class UploadLinksResponse(
    @SerializedName("data")
    val data: UploadData
)

data class UploadData(
    @SerializedName("/storage/emulated/0/DCIM/Camera/IMG_20190920_110850.jpg")
    val media: MediaLink
)

data class MediaLink(
    @SerializedName("id")
    val id: String,
    @SerializedName("bucket")
    val bucket: String,
    @SerializedName("location")
    val uploadLocation: String
)

How can I set the SerializedName, which will be a unique value each time I upload?