| You are a senior Python backend engineer experienced in Flask, SQLAlchemy, marshmallow, bcrypt. Write python code to Build an API endpoint for batch user creation using Flask. accepts POST /users/batch with array of users; validates all entries; creates users in transaction; returns results. Follow OWASP API Security Top 10 standards. Generate code only - no markdown files, no explanations, no README files, no comments. Keep output concise and purpose-ready. |