json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "type": "object",
      "title": "Jsst ND",
      "description": "An explanation about the purpose of this instance.",
      "properties": {
          "outer1": {
              "type": "object",
              "title": "Outer1 schema.",
              "description": "An explanation about the purpose of this instance.",
              "properties": {
                  "innerK1": {
                      "type": "string",
                      "title": "InnerK1 schema.",
                      "description": "An explanation about the purpose of this instance."
                  },
                  "innerK2": {
                      "type": "integer",
                      "title": "InnerK2 schema.",
                      "description": "An explanation about the purpose of this instance."
                  }
              },
              "required": [
                  "innerK1",
                  "innerK2"
              ]
          },
          "outer2": {
              "type": "string",
              "title": "Outer2 schema.",
              "description": "An explanation about the purpose of this instance."
          }
      },
      "required": [
          "outer1",
          "outer2"
      ]
  }