# ERROR: Invalid version specifier: '>=1.0, <2.0' (trailing comma)

- **ID:** `python/pip-invalid-version-specifier`
- **Domain:** python
- **Category:** config_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The version specifier contains a trailing comma or other syntax errors per PEP 440.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.8 | active | — | — |
| 3.9 | active | — | — |
| 3.10 | active | — | — |
| 3.11 | active | — | — |
| 3.12 | active | — | — |

## Workarounds

1. **Remove the trailing comma** (95% success)
   ```
   Change to '>=1.0,<2.0' (no space after comma)
   ```
2. **Use a comma-separated list without trailing punctuation** (90% success)
   ```
   pip install 'package>=1.0,<2.0'
   ```

## Dead Ends

- **Adding more spaces around the comma** — The trailing comma is the issue, not spacing. (90% fail)
- **Using semicolon instead of comma** — Semicolons are not valid version specifier separators. (80% fail)