使用pip3升级Python依赖遇SSL错误：UNSAFE_LEGACY_RENEGOTIATION_DISABLED

我正在使用QGIS 3.34.9附带安装的OSGeo4W（基于Python 3.12.4）升级Python依赖，主要是remotior-sensus。按照官方文档步骤操作，已下载依赖但无法安装。执行命令：

pip3 install --upgrade remotior-sensus scikit-learn torch

后出现以下错误：

Requirement already satisfied: remotior-sensus in c:\progra~1\qgis33~1.9\apps\python312\lib\site-packages (0.3.5)
WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/remotior-sensus/
WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/remotior-sensus/
WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/remotior-sensus/
WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/remotior-sensus/
WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/remotior-sensus/
Could not fetch URL https://pypi.org/simple/remotior-sensus/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/remotior-sensus/ (Caused by SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))) - skipping
WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/scikit-learn/
WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/scikit-learn/
WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/scikit-learn/
WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/scikit-learn/
WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))': /simple/scikit-learn/
Could not fetch URL https://pypi.org/simple/scikit-learn/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/scikit-learn/ (Caused by SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))) - skipping
ERROR: Could not find a version that satisfies the requirement scikit-learn (from versions: none)
ERROR: No matching distribution found for scikit-learn
Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError(SSLError(1, '[SSL: UNSAFE_LEGACY_RENEGOTIATION_DISABLED] unsafe legacy renegotiation disabled (_ssl.c:1000)'))) - skipping

这个错误源于Python 3.12默认禁用了不安全的旧版SSL协商机制，导致无法正常连接PyPI。以下是几种可行的解决方案：

方法1：临时设置环境变量绕过SSL校验 #

打开OSGeo4W Shell，依次执行以下命令，再运行pip安装：

set SSL_CERT_FILE=C:\PROGRA~1\QGIS33~1.9\apps\Python312\Lib\site-packages\certifi\cacert.pem
set PYTHONHTTPSVERIFY=0
set SSL_ENABLE_EARLY_DATA=0
pip3 install --upgrade remotior-sensus scikit-learn torch

方法2：配置pip信任PyPI主机 #

1. 在用户目录下创建pip文件夹，路径示例：C:\Users\[你的用户名]\pip
2. 在该文件夹内新建pip.ini文件，写入以下内容：

[global]
trusted-host = pypi.org
               files.pythonhosted.org

保存后重新运行pip安装命令即可。

方法3：使用国内PyPI镜像源 #

直接指定国内镜像源，绕开SSL协商问题，执行命令：

pip3 install --upgrade remotior-sensus scikit-learn torch -i https://pypi.tuna.tsinghua.edu.cn/simple

方法4：手动安装本地已下载的依赖包 #

既然已下载好依赖包，直接用pip安装本地文件，替换命令中的xxx为实际版本号和文件路径：

pip3 install [本地路径]\remotior-sensus-xxx.whl [本地路径]\scikit-learn-xxx.whl [本地路径]\torch-xxx.whl

内容的提问来源于stack exchange，提问作者user25730