docker-compose启动报错，解决方案

1. [root@cache1 www]# docker-compose
   Traceback (most recent call last):
   File "/usr/bin/docker-compose", line 5, in <module>
   from pkg_resources import load_entry_point
   File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 3011, in <module>
   parse_requirements(__requires__), Environment()
   File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 626, in resolve
   raise DistributionNotFound(req)
   pkg_resources.DistributionNotFound: backports.ssl-match-hostname>=3.5

2. pip install --upgrade pip # 先升级下pip
3. pip install docker-compose
5. # 执行如下命令
6. docker-compose --help
7. # 报如下错误：
8. Traceback (most recent call last):
9. File "/usr/bin/docker-compose", line 5, in <module>
10. from pkg_resources import load_entry_point
11. File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 3011, in <module>
12. parse_requirements(__requires__), Environment()
13. File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 626, in resolve
14. raise DistributionNotFound(req)
15. pkg_resources.DistributionNotFound: backports.ssl-match-hostname>=3.5
17. # 解决方法：
18. pip install --upgrade backports.ssl_match_hostname