# ERROR: packaging.requirements.InvalidRequirement: Expected end of string, got ';' in requirement 'requests>=2.25; extra == "security"'

- **ID:** `python/packaging-requirement-parsing-error`
- **Domain:** python
- **Category:** data_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The requirement string uses extras syntax incorrectly; extras must be enclosed in square brackets, not separated by semicolon.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.9 | active | — | — |
| 3.10 | active | — | — |

## Workarounds

1. **Use correct extras syntax with square brackets** (95% success)
   ```
   Write: 'requests[security]>=2.25' (extras inside brackets).
   ```
2. **Use environment markers for conditional dependencies** (90% success)
   ```
   Write: 'requests>=2.25; extra == "security"' but note that this is for markers, not extras. For extras, use brackets.
   ```

## Dead Ends

- **Removing the semicolon and extra entirely** — Loses the conditional requirement. (70% fail)
- **Using a comma instead of semicolon** — Comma is not valid for extras syntax. (80% fail)