OpenAI API error: "Invalid parameter: 'response_format' of type 'json_schema' is not supported with model version `gpt-4-turbo`"

From the main page and official documentation, OpenAI clearly mentioned we can use the response_format as follows:

What I’m trying in Postman is the following:

{
    "instructions": "You are a personal math tutor. When asked a question, write and run Python code to answer the question.",
    "name": "Math Tutor",
    "tools": [{"type": "code_interpreter"}],
    "model": "GPT-4 Turbo",
    "type": "json_schema"
 }

But I got the following error:

{
    "error": {
        "message": "Unknown parameter: 'type'.",
        "type": "invalid_request_error",
        "param": "type",
        "code": "unknown_parameter"
    }
}

After asking some popular LLM models, they suggested to try the following in Postman:

{
    "instructions": "You are a personal math tutor. When asked a question, write and run Python code to answer the question.",
    "name": "Math_Tutor",
    "tools": [{"type": "code_interpreter"}],
    "model": "gpt-4-turbo",
    "response_format": {
        "type": "json_schema",
        "json_schema": {
            "strict": true,
            "name": "MathTutorResponse",
            "schema": {
                "type": "object",
                "properties": {
                    "result": {
                        "type": "number"
                    },
                    "explanation": {
                        "type": "string"
                    }
                },
                "required": ["result", "explanation"],
                "additionalProperties": false
            }
        }
    }
}

But I got the following error:

{
    "error": {
        "message": "Invalid parameter: 'response_format' of type 'json_schema' is not supported with model version `gpt-4-turbo`.",
        "type": "invalid_request_error",
        "param": "response_format",
        "code": null
    }
}

Am I missing anything here? Please provide me with a snippet where I can configure assistant output to be in JSON format.