Linux下的Python3.6报错ModuleNotFoundError: No module named '_ssl'

在python3中导入ssl模块时报如下错误：

Python 3.6.3 (default, Nov 19 2018, 14:18:18)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-28)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import ssl
Traceback (most recent call last):
  File "", line 1, in <module>
  File "/usr/local/python3/lib/python3.6/ssl.py", line 101, in <module>
    import _ssl             # if we can't import it, let the error propagate
ModuleNotFoundError: No module named '_ssl'

解决方法如下：

先检测 系统 安装 OpenSSL

yum install openssl-devel bzip2-devel expat-devel gdbm-devel readline-devel sqlite-devel gcc gcc-c++ openssl-devel

1、进入Python安装目录。
2、然后到 Modules 目录, 找到Setup.dist文件，将下面几行的注释去掉（下图已去掉）。
vim Setup.dist （约50%处）

3、编译安装

./configure --prefix=/usr/local/python3
或者
cd python3.6
./configure

make
make install

这里可能又出现问题：
1）Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
可使用以下命令即可解决

yum provides '*/applydeltarpm'  
yum install deltarpm -y

2）File “/usr/libexec/urlgrabber-ext-down”, line 28 except OSError, e:

vim urlgrabber-ext-down

将#！ /usr/bin/python
改为#！/usr/bin/python2然后保存退出即可。

4.删除旧的软连接，创建新的软连接

rm -rf /usr/bin/python3
ln -s /usr/local/bin/python3.6 /usr/bin/python3

测试成功

好事多磨，终于成功，啊哈哈哈

Python 3.6.3 (default, Nov 21 2018, 22:23:54)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-28)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import ssl
>>>