Sage安装pycrypto时出现Crypto模块缺失及pip SSL报错问题

Sage环境运行代码时抛出No module named 'Crypto'导入错误，常规处理方案为执行安装命令：

sage --pip install pycrypto

执行上述命令时触发SSL连接错误，无法完成包拉取安装，完整报错输出如下：

WARNING: pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pycrypto/
WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pycrypto/
WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pycrypto/
WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pycrypto/
WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError("Can't connect to HTTPS URL because the SSL module is not available.")': /simple/pycrypto/
Could not fetch URL https://pypi.org/simple/pycrypto/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pycrypto/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping
ERROR: Could not find a version that satisfies the requirement pycrypto (from versions: none)
ERROR: No matching distribution found for pycrypto
WARNING: pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
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("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping

• 核心根因为Sage内置的Python运行环境未编译SSL模块，无法建立HTTPS连接访问PyPI源拉取安装包，和pycrypto包本身是否存在无关。
• 额外说明：pycrypto已停止维护多年，存在已知安全漏洞，当前推荐使用其兼容维护分支pycryptodome，导入路径完全一致，原有代码无需修改即可正常运行。

1. 先安装系统层面的OpenSSL依赖，根据自身操作系统执行对应命令：
   • Debian/Ubuntu系列发行版：

   sudo apt update && sudo apt install -y libssl-dev openssl
   

   • RHEL/CentOS/Fedora系列发行版：

   sudo dnf install -y openssl openssl-devel
   # CentOS 7版本将dnf替换为yum执行即可
   

   • macOS（Homebrew环境）：

   brew install openssl
   

2. 重新编译Sage内置的Python环境，使其识别到系统安装的OpenSSL依赖：

sage -i python3

3. 编译完成后，执行命令安装兼容版加密库：

sage --pip install pycryptodome

若重新编译内置Python后仍报SSL模块缺失错误，可直接下载对应系统的Sage官方完整二进制安装包覆盖安装，默认预装全部依赖，不会出现SSL模块缺失问题。

4. 安装完成后进入Sage交互环境，执行import Crypto验证，无报错即代表修复完成。

内容的提问来源于stack exchange，提问作者Luke