# 错误：找不到满足要求的版本 somepackage==999.0.0（可用版本：0.1、0.2、1.0）

- **ID:** `python/pip-no-matching-distribution`
- **领域:** python
- **类别:** config_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

指定的版本约束与 PyPI 或配置的索引上的任何可用版本不匹配。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| 3.8 | active | — | — |
| 3.9 | active | — | — |
| 3.10 | active | — | — |
| 3.11 | active | — | — |

## 解决方案

1. **Check available versions and use a valid one** (95% 成功率)
   ```
   `pip index versions somepackage` then install a valid version, e.g., `pip install somepackage==1.0`
   ```
2. **Use a version range or no version constraint** (90% 成功率)
   ```
   `pip install somepackage>=1.0` or simply `pip install somepackage`
   ```

## 无效尝试

- **Assuming the package name is correct but using a typo in version** — The version string is exact; even a minor typo (e.g., 999.0.0 vs 999.0) will fail. (50% 失败率)
- **Running `pip install --upgrade` without specifying the correct version** — If the package is not installed, --upgrade has no effect; also, it won't fix an invalid version constraint. (80% 失败率)