# ValueError: The name 'auth' is already registered for this blueprint. Use 'name=' to provide a unique name.

- **ID:** `python/flask-blueprint-name-collision`
- **Domain:** python
- **Category:** runtime_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

Registering two blueprints with the same name in the same app.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 2.x | active | — | — |
| 3.x | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   bp = Blueprint('auth_v2', __name__)
   ```
2. **** (90% success)
   ```
   app.register_blueprint(bp, name='auth_v2')
   ```

## Dead Ends

- **** — The blueprint's internal name attribute is what matters, not the variable. (60% fail)
- **** — Name collision still occurs. (90% fail)