| Write python code to Create an API endpoint for request signing with HMAC using Flask. accepts requests with HMAC signature in header; validates signature against request body; rejects invalid signatures; returns 401 on failure. Structure the project as: app/, middleware/hmac_validator.py, utils/signer.py. Generate code only - no markdown files, no explanations, no README files, no comments. Keep output concise and purpose-ready. |