extra={"unsubscribe_link": "https://example.com/unsubscribe"})
    pdf = message_builder.html_to_pdf(res.text)
    import base64
    return {"pdf_base64": base64.b64encode(pdf).decode(), "size_bytes": len(pdf),
            "engine": "WeasyPrint"}
209 app/api/routers/templates.py