{ "key0" :[{
  "key1": "34",
  "key2": "34",
  "key3": {
    "key3_1": "0",
    "key3_2": "0"
  },
  "key4": "56"    },
{
  "key1": "14",
  "key2": "78",
  "key3": {
    "key3_1": "0",
    "key3_2": "0"
  },
  "key4": "676"
}]
  "key2": "value2"
}

implicit val contentReader = (
  (__  "key0").read[List[Map[String, String]]] and
  (__  "key4").read[String]
  )(Content)

val json : JsValue = Json.parse(content)
val contentResult = json.as[Content]