{
    "content": {
        "avatar_url": null,
        "displayname": "example",
        "membership": "join"
    },
    "event_id": "$151800140517rfvjc:localhost",
    "membership": "join",
    "origin_server_ts": 1518001405556,
    "sender": "@example:localhost",
    "state_key": "@example:localhost",
    "type": "m.room.member",
    "unsigned": {
        "age": 2970366338,
        "replaces_state": "$151800111315tsynI:localhost"
    }
}