顺便问一下，我使用的是windows，所以我必须安装visual studio吗？(py) D:\python>pip install simplejson

Downloading/unpacking simplejson

Downloading simplejson-2.6.2.tar.gz (53kB): 53kB downloaded

Running setup.py egg_info for package simplejson

Installing collected packages: simplejson

Running setup.py install for simplejson

building 'simplejson._speedups' extension

***************************************************************************

警告：无法编译C扩展，未启用加速功能。Failure information, if any, is above.

I'm retrying the build without the C extension now.

***************************************************************************

***************************************************************************

WARNING: The C extension could not be compiled, speedups are not enabled.

Plain-Python installation succeeded.

***************************************************************************

Successfully installed simplejson

Cleaning up...