解决You are using pip version 9.0.1, however version 18.0 is available. You should consider upgrading
Linux版本：Centos7 64位
安装scrapy框架用于写python爬虫时出现警告：
You are using pip version 9.0.1, however version 18.0 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
意思是版本低，要更新新的版本
解决方法：
[[email protected] Python3.6.3]# python3 -m pip install --upgrade pip
好了，版本升级成功，再次安装scrapy
[[email protected] Python3.6.3]# pip3 install scrapy