CentOS python升级到3.5时yum报错

File "/usr/bin/yum", line 30
    except KeyboardInterrupt, e:
                            ^
SyntaxError: invalid syntax

解决步骤：

#vi /usr/bin/yum

将#!/usr/bin/python改为#!/usr/bin/python2.7

退出保存

相关错误：

【https://linuxconfig.org/how-to-switch-between-python-versions-on-fedora-linux】

Similarly: Error message:

Downloading packages:
  File "/usr/libexec/urlgrabber-ext-down", line 28
    except OSError, e:
                  ^
SyntaxError: invalid syntax
Exiting on user cancel

The issue is also related to Python 3 set as a default global version. To fix this error update /usr/libexec/urlgrabber-ext-down script:

# vi /usr/libexec/urlgrabber-ext-down
FROM:
#!/usr/bin/python
TO:
#!/usr/bin/python2.7