json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema",
      "title": "Schema of Net",
      "type": "object",
      "required": [
          "vars",
          "params",
          "blocks"
      ],
      "properties": {
          "vars": {
              "description": "A dictionary that its keys are name of variables and its valus are multi-dimensional arrays",
              "type": "object"
          },
          "params": {
              "description": "Name of `vars`, which are parameters",
              "type": "array",
              "items": {
                  "type": "string"
              }
          },
          "blocks": {
              "description": "A dictionary that it's keys are output vars and values are {'inputs': 'string array', 'function': 'string'}",
              "type": "object"
          }
      }
  }