{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "oneOf": [
        {
            "properties": {
                "@level": {
                    "const": "0"
                },
                "@classId": {
                    "const": "1"
                },
                "#text": {
                    "const": "Technical unit groups"
                }
            }
        },
        {
            "properties": {
                "@level": {
                    "const": "0"
                },
                "@classId": {
                    "const": "2"
                },
                "#text": {
                    "const": "Chemical composition unit groups"
                }
            }
        },
        {
            "properties": {
                "@level": {
                    "const": "0"
                },
                "@classId": {
                    "const": "3"
                },
                "#text": {
                    "const": "Economic unit groups"
                }
            }
        },
        {
            "properties": {
                "@level": {
                    "const": "0"
                },
                "@classId": {
                    "const": "4"
                },
                "#text": {
                    "const": "Other unit groups"
                }
            }
        }
    ]
}