json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "description": "A parsed date object. This allows us to represent not just normal dates, but also partial dates too",
      "type": "object",
      "properties": {
          "year": {
              "type": "number",
              "description": "year part as YYYY"
          },
          "month": {
              "type": "number",
              "description": "month part of date in numbers e.g. 11 for November, 4 for April"
          },
          "day": {
              "type": [
                  "number",
                  "null"
              ],
              "description": "day part of date in numbers"
          }
      },
      "additionalProperties": false,
      "anyOf": [
          {
              "required": [
                  "year",
                  "month"
              ]
          },
          {
              "required": [
                  "month",
                  "day"
              ]
          }
      ]
  }