How do I map API Gateway responses to HTTP status codes?

import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";

// Create an API Gateway
const api = new aws.apigateway.RestApi("myApi", {
    description: "API for demonstrating response mapping",
});

// Create a resource
const resource = new aws.apigateway.Resource("myResource", {
    restApi: api.id,
    parentId: api.rootResourceId,
    pathPart: "example",
});

// Create a method for the resource
const method = new aws.apigateway.Method("myMethod", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: "GET",
    authorization: "NONE",
});

// Create a method response for HTTP 200 status
const methodResponse200 = new aws.apigateway.MethodResponse("methodResponse200", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: method.httpMethod,
    statusCode: "200",
    responseModels: {
        "application/json": "Empty",
    },
});

// Create a method response for HTTP 400 status
const methodResponse400 = new aws.apigateway.MethodResponse("methodResponse400", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: method.httpMethod,
    statusCode: "400",
    responseModels: {
        "application/json": "Error",
    },
});

// Create an integration for the method
const integration = new aws.apigateway.Integration("myIntegration", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: method.httpMethod,
    type: "MOCK",
    requestTemplates: {
        "application/json": `{
            "statusCode": 200
        }`,
    },
});

// Create an integration response for HTTP 200 status
const integrationResponse200 = new aws.apigateway.IntegrationResponse("integrationResponse200", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: method.httpMethod,
    statusCode: methodResponse200.statusCode,
    responseTemplates: {
        "application/json": `{
            "message": "Success"
        }`,
    },
});

// Create an integration response for HTTP 400 status
const integrationResponse400 = new aws.apigateway.IntegrationResponse("integrationResponse400", {
    restApi: api.id,
    resourceId: resource.id,
    httpMethod: method.httpMethod,
    statusCode: methodResponse400.statusCode,
    selectionPattern: ".*\\[400\\].*",
    responseTemplates: {
        "application/json": `{
            "error": "Bad Request"
        }`,
    },
});

// Deploy the API
const deployment = new aws.apigateway.Deployment("myDeployment", {
    restApi: api.id,
    stageName: "dev",
}, { dependsOn: [integration] });

// Export the API endpoint
export const apiEndpoint = deployment.invokeUrl;