docs: clarify usage in first example

Author: mnorlin

README.md

@@ -7,6 +7,9 @@ It is primarily focused on using the TypeScript definitions generated by [openap
 ## Example
 
 ```ts
+import createFetch from "typed-api-fetch";
+import { paths } from "./petstore-schema.d.ts"; // generated by openapi-typescript
+
 const fetch = createFetch<paths>({ baseUrl: "https://petstore3.swagger.io" });
 
 const response = await fetch(
@@ -19,10 +22,16 @@ const response = await fetch(
   },
 );
 
-const data = await response.json();
+if (response.ok) {
+  const dataOk = await response.json(); // Infered type of HTTP 2XX status codes
 
-console.log(data.name);
-console.log(data.age); // ❌ property 'age' does not exist
+  console.log(dataOk.name);
+  console.log(dataOk.age); // ❌ property 'age' does not exist
+}
+
+if (response.status === 404) {
+  const data404 = await response.json(); // Infered type on HTTP 404 status responses
+}
 ```
 
 ## Install

test/openapi-typescript/fetch-factory.test.ts

@@ -1,4 +1,4 @@
-import createFetch, { FetchMethods } from "../../src/openapi-typescript";
+import createFetch from "../../src/openapi-typescript";
 import { paths, components } from "./test-data/petstore-openapi3";
 import { IsEqual } from "../test-tools";