update readme

Author: c4spar

README.md

@@ -13,18 +13,22 @@ Amazon S3 for Deno
 ```ts
 import { S3, S3Bucket } from "https://deno.land/x/[email protected]/mod.ts";
 
-// Create a new bucket.
+// Create a S3 instance.
 const s3 = new S3({
   accessKeyID: Deno.env.get("AWS_ACCESS_KEY_ID")!,
   secretKey: Deno.env.get("AWS_SECRET_ACCESS_KEY")!,
   region: "us-east-1",
   endpointURL: Deno.env.get("S3_ENDPOINT_URL"),
 });
 
-const myBucket = await s3.createBucket("my-bucket", { acl: "private" });
+// Create a new bucket.
+let bucket = await s3.createBucket("test", { acl: "private" });
+
+// Get an existing bucket.
+bucket = s3.getBucket("test");
 
-// Create a bucket instance from an existing bucket.
-const bucket = new S3Bucket({
+// Create a bucket instance manuely.
+bucket = new S3Bucket({
   accessKeyID: Deno.env.get("AWS_ACCESS_KEY_ID")!,
   secretKey: Deno.env.get("AWS_SECRET_ACCESS_KEY")!,
   bucket: "test",