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
