Convert text to speech with OpenAI

How It Works This workflow sends an HTTP request to OpenAI's Text-to-Speech (TTS) model, returning an .mp3 audio recording of the provided text. This template is meant to be adapted for your individual use case, and requires a valid OpenAI credential. Gotchas Per OpenAI's Usage Policies, you must provide a clear disclosure to end users that the TTS voice they are hearing is AI-generated and not a human voice, if you are using this workflow to provide audio output to users.

Help me set up the n8n workflow "Convert text to speech with OpenAI" (https://n8n.io/workflows/2092). It uses: HTTP Request. Import the template JSON into my n8n instance, list every credential I need to create, and walk me through testing it.