我已经在我的本地机器上成功安装了Python 3.4和Python 3.6，但无法安装带有pip3的包。
当我执行pip3 install <package>时，我得到以下SSL相关错误:
pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.
Collecting <package>
Could not fetch URL https://pypi.python.org/simple/<package>/: There was a problem confirming the ssl certificate: Can't connect to HTTPS URL because the SSL module is not available. - skipping
Could not find a version that satisfies the requirement <package> (from versions: )
No matching distribution found for <package>
如何修复我的Python3。pip install <package>?
ssl模块是用于访问操作系统(OS)套接字(Lib/ssl.py)的TLS/ ssl包装器。因此，当ssl模块不可用时，可能是您没有安装OS OpenSSL库，或者在安装Python时没有找到这些库。让我们假设这是后面的情况(也就是说:你已经安装了OpenSSL，但在安装Python时没有正确链接它们)。
我还假定您是从源代码安装的。如果你是从二进制文件(例如:windows .exe文件)，或包(Mac .dmg，或Ubuntu apt)安装，在安装过程中你可以做的不多。
在配置python安装的步骤中，您需要指定将使用OS OpenSSL进行链接的位置:
# python 3.8 beta
./configure --with-openssl="your_OpenSSL root"
那么，在哪里可以找到已安装的OpenSSL目录呢?
# ubuntu
locate ssl.h | grep '/openssl/ssl.h'
/home/user/.linuxbrew/Cellar/openssl/1.0.2r/include/openssl/ssl.h
/home/user/envs/py37/include/openssl/ssl.h
/home/user/miniconda3/envs/py38b3/include/openssl/ssl.h
/home/user/miniconda3/include/openssl/ssl.h
/home/user/miniconda3/pkgs/openssl-1.0.2s-h7b6447c_0/include/openssl/ssl.h
/home/user/miniconda3/pkgs/openssl-1.1.1b-h7b6447c_1/include/openssl/ssl.h
/home/user/miniconda3/pkgs/openssl-1.1.1c-h7b6447c_1/include/openssl/ssl.h
/usr/include/openssl/ssl.h
您的系统可能与我的不同，但正如您在这里看到的，我安装了许多不同的openssl库。在撰写本文时，python 3.8期望openssl 1.0.2或1.1:
Python要求使用X509_VERIFY_PARAM_set1_host()与OpenSSL 1.0.2或1.1兼容的libssl。
因此，您需要验证哪些已安装的库可以用于链接
/usr/bin/openssl version
OpenSSL 1.0.2g 1 Mar 2016
./configure --with-openssl="/usr"
make && make install
您可能需要尝试一些库，或者安装一个新的库，以找到适合您的Python和操作系统的库。
I finally solve this issue. These are the detail of my env:
Version of Python to install: 3.6.8
OS: Ubuntu 16.04.6 LTS
Root access: No
Some people suggest to install libssl-dev, but it did not work for me. I follow this link and I fixed it!
In short, I download, extract, build, and install OpenSSL (openssl-1.1.1b.tar.gz). Then, I modify .bashrc file follow this link.
Next, I download and extract Python-3.6.8.tgz. I edit Modules/Setup.dist to modify SSL path (lines around #211). I did ./configure --prefix=$HOME/opt/python-3.6.8, make and make install. Last, I modify my .bashrc. Notice that I do not include --enable-optimizations in ./configure.
