解决Python找不到ssl模块问题 No module named _ssl的方法

python安装完毕后，提示找不到ssl模块：

[www@pythontab.com ~]$ python
Python 2.7.15 (default, Oct 23 2018, 18:08:43)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-23)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import ssl
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/local/python27/lib/python2.7/ssl.py", line 60, in <module>
import _ssl # if we can't import it, let the error propagate
ImportError: No module named _ssl
>>>

解决方法：

1. 查看openssl安装包，发现缺少openssl-devel包

[www@pythontab.com ~]$ rpm -aq|grep openssl
openssl-0.9.8e-20.el5
openssl-0.9.8e-20.el5
[www@pythontab.com ~]$

2. yum安装openssl-devel

[www@pythontab.com ~]$ yum install openssl-devel -y
#查看安装结果
[www@pythontab.com ~]$ rpm -aq|grep openssl
openssl-devel-1.0.1e-57.el6.x86_64
openssl-1.0.1e-57.el6.x86_64

3. 重新编译python

修改Setup文件

vi /src/Python-2.7.15/Modules/Setup

修改结果如下：

# Socket module helper for socket(2)
_socket socketmodule.c timemodule.c
# Socket module helper for SSL support; you must comment out the other
# socket line above, and possibly edit the SSL variable:
#SSL=/usr/local/ssl
_ssl _ssl.c \
-DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
-L$(SSL)/lib -lssl -lcrypto

4. 重新编译

进入源码目录，重新编译安装

[www@pythontab.com ~]$ cd /src/Python-2.7.15/
[www@pythontab.com ~]$ make
[www@pythontab.com ~]$ make install

5. 测试，已可正常使用。

[www@pythontab.com ~]$ python
Python 2.7.15 (default, Oct 23 2018, 19:08:43)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-23)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import ssl
>>>

注：如需保留旧版本的就不需要执行 6 .7两部

6 重命名旧版本的python依赖

ll /usr/bin | grep python
mv /usr/bin/python /usr/bin/python2.7

7 删除旧的软链接，创建新的软链接到最新的python

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

使用yum命令报错File "/usr/bin/yum", line 30 except KeyboardInterrupt, e:

问题出现原因：

yum包管理是使用python2.x写的，将python2.x升级到python3.1.3以后，由于python版本语法兼容性导致问题出现

解决办法：

修改yum配置文件，将python版本指向以前的旧版本

# vi /usr/bin/yum
#!/usr/bin/python2.7
修改urlgrabber-ext-down文件，更改python版本

# vi /usr/libexec/urlgrabber-ext-down
#!/usr/bin/python2.7
Could not fetch URL https://pypi.python.org/simple/six/: There was a problem confirming the ssl certificate: Can't connect to HTTPS URL because the SSL module is not available. - skipping

如需安装pip

下载相关文件

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

执行

/usr/local/python/bin/python3 get-pip.py

添加环境变量

vim ~/.bash_profile

添加下面这条参数

export PATH=/usr/local/python/bin:$PATH

保存

source ~/.bash_profile

测试

执行

[root@huo ~]# python3
Python 3.6.5 (default, Apr 1 2018, 20:41:34)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-16)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>

执行脚本如下:

vim install_python.sh

#!/bin/bash
echo "正在安装相关组件"
yum install -y openssl-devel bzip2-devel expat-devel gdbm-devel readline-devel sqlite-devel gcc-c++ gcc openssl-devel

echo "下载安装包"
wget https://www.python.org/ftp/python/3.6.5/Python-3.6.5.tgz

echo "正在解压安装包"
tar -xf Python-3.6.5.tgz -C /root/ && cd /root/Python-3.6.5/

echo "添加ssl支持"
cat >> /root/Python-3.6.5/Modules/Setup.dist <<"EOF"
_socket socketmodule.c

SSL=/usr/local/ssl
_ssl _ssl.c \
-DUSE_SSL -I$(SSL)/include -I$(SSL)/include/openssl \
-L$(SSL)/lib -lssl -lcrypto
EOF

echo "正在编译安装Python"
./configure --prefix=/usr/local/python && make && make install
cd /root

echo "删除安装包"
rm -rf /root/Python-3.6.5.tgz && rm -rf /root/Python-3.6.5

echo "正在添加环境变量"
echo "export PATH=/usr/local/python/bin:$PATH">> ~/.bash_profile
source ~/.bash_profile

echo "安装完成,请执行python3进行测试"

来源：https://www.pythontab.com/html/2018/pythonjichu_1024/1366.html