Python3 要求openssl 1.1.1以上，否则会报如下错误：

pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.

安装openssl

./config --prefix=/usr/local/openssl1.1.1b --shared

make

make install

编辑/etc/ld.so.conf文件，加入以下行

/usr/local/openssl1.1.1b/lib

然后运行ldconfig

#yum install zlib libffi-devel gcc -y

#./configure --prefix=/usr/local/python373 --with-openssl=/usr/local/openssl1.1.1b

#make && make install