{
    "content": {
        "topic": "😀"
    },
    "event_id": "$151957878228ssqrJ:localhost",
    "origin_server_ts": 1519578782185,
    "sender": "@example:localhost",
    "state_key": "",
    "type": "m.room.topic",
    "unsigned": {
      "age": 1392989709,
      "prev_content": {
        "topic": "test"
      },
      "prev_sender": "@example:localhost",
      "replaces_state": "$151957069225EVYKm:localhost"
    }
}