This example demonstrates how to compute an API signature for the Common Crawl Index API using the Python standard library’s `md5` module. It shows the required process of concatenating a project secret with a lowercase user email, then hashing that combined string to produce a hex digest. The code explicitly uses `md5.new()` and `update()` to generate the signature, printing the final `hexdigest()` result. The visualization highlights the exact data inputs—the hardcoded secret and email—and the output signature, making the authentication flow transparent.