总所周知 ujson 要比 json 模块高效，可是安装也太麻烦了。之前在 Windows7 中使用 Python2.x 的第三方模块 ujson ，使用pip install ujson 安装时没有问题的，换成 Windows10 的时候报错了。

报错如下：

C:\>pip install ujson
Collecting ujson
  Downloading https://files.pythonhosted.org/packages/16/c4/79f3409bc710559015464e5f49b9879430d8f87498ecdc335899732e5377/ujson-1.35.tar.gz (192kB)
    100% |████████████████████████████████| 194kB 64kB/s
Building wheels for collected packages: ujson
  Running setup.py bdist_wheel for ujson ... error
  Complete output from command c:\programdata\anaconda3\python.exe -u -c "import setuptools, tokenize;__file__='C:\\Users\\niko\\AppData\\Local\\Temp\\pip-install-6naov7i3\\ujson\\setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d C:\Users\niko\AppData\Local\Temp\pip-wheel-v4jxz935 --python-tag cp36:
  running bdist_wheel
  running build
  running build_ext
  building 'ujson' extension
  error: Microsoft Visual C++ 14.0 is required. Get it with "Microsoft Visual C++ Build Tools": https://visualstudio.microsoft.com/downloads/

  ----------------------------------------
  Failed building wheel for ujson
  Running setup.py clean for ujson
Failed to build ujson
Installing collected packages: ujson
  Running setup.py install for ujson ... error
    Complete output from command c:\programdata\anaconda3\python.exe -u -c "import setuptools, tokenize;__file__='C:\\Users\\niko\\AppData\\Local\\Temp\\pip-install-6naov7i3\\ujson\\setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record C:\Users\niko\AppData\Local\Temp\pip-record-dnr78gng\install-record.txt --single-version-externally-managed --compile:
    running install
    running build
    running build_ext
    building 'ujson' extension
    error: Microsoft Visual C++ 14.0 is required. Get it with "Microsoft Visual C++ Build Tools": https://visualstudio.microsoft.com/downloads/

    ----------------------------------------
Command "c:\programdata\anaconda3\python.exe -u -c "import setuptools, tokenize;__file__='C:\\Users\\niko\\AppData\\Local\\Temp\\pip-install-6naov7i3\\ujson\\setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record C:\Users\niko\AppData\Local\Temp\pip-record-dnr78gng\install-record.txt --single-version-externally-managed --compile" failed with error code 1 in C:\Users\niko\AppData\Local\Temp\pip-install-6naov7i3\ujson\

大体意思就是缺少编译ujson的C++编译工具，经过查阅得知：

Python 2.7需要Microsoft Visual C++ 9.0的库
Python 3.6需要Microsoft Visual C++ 14.0的库

很显然，解决方案只有两种了：

• 下载whl文件直接安装（Python2和Python3适用）

  下载地址：https://www.lfd.uci.edu/~gohlke/pythonlibs/
  在这里可以搜索你想要的库!!!
  使用 pip install xxx.whl 安装即可。

• 下载Microsoft Visual C++ Build Tools（Python3适用）

  下载微软的C++编译工具，CSDN上下载竟然花钱，气死我了...我特么还是学生呢...在这里下载吧，免费的：http://down.51cto.com/data/2452424
  下载完成使用管理员权限打开，安装Windows10SDK和.NET框架即可!!!