“Win +R”打开cmd终端，如果直接在里面使用pip命令的时候，要么出现“syntax invalid”，要么出现：
'pip' is not recognized as an internal or external command, operable program or batch file.
此时需要将C:\Python27\Scripts添加到系统环境变量，我顺便将C:\Python27\python.exe也添加进了系统环境变量，要保证echo %PATH%能看到对应的目录。
再使用pip install pyserial就可以安装serial模块了，不过我的右如下提示，说我的版本过旧：
C:\Users\h144197>pip install pyserialRequirement already satisfied (use --upgrade to upgrade): pyserial in c:\python27\lib\site-packagesYou are using pip version 8.1.1, however version 9.0.1 is available.You should consider upgrading via the 'python -m pip install --upgrade pip' command.
照着提示做就好了，类似于linux下的shell。
C:\Users\h144197>python -m pip install --upgrade pipCollecting pipDownloading pip-9.0.1-py2.py3-none-any.whl (1.3MB)100% |¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€¨€| 1.3MB 80kB/sInstalling collected packages: pipFound existing installation: pip 8.1.1Uninstalling pip-8.1.1:Successfully uninstalled pip-8.1.1Successfully installed pip-9.0.1
现在就可以使用pip安装模块了。
爽吧。。。
