Pyconfig.h - Cannot open include file: 'io.h': No such file or directory

Reference Information:

• I am new to python / Cpp and I am trying to install the python package python-crfsuite which needs to compile VS.

• I installed Anaconda3, pyhon3.6 all community installer VS2017 (because I think it's better because I'll use the compiler the VS: cl.exe
  
  )

• I already ran vcvarsall.bat
  
  

• All the commands I run are in admin

Process:

When I try pip install

python-crfsuite it gives me an error:

C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.10.25017\bin\HostX86\x86\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -Icrfsuite/include/ -Icrfsuite/lib/cqdb/include -Iliblbfgs/include -Ipycrfsuite -Icrfsuite/win32 -Iinclude "-IC:\Program Files\Anaconda3\include" "-IC:\Program Files\Anaconda3\include" /EHsc /Tppycrfsuite/_pycrfsuite.cpp /Fobuild\temp.win-amd64-3.6\Release\pycrfsuite/_pycrfsuite.obj _pycrfsuite.cpp c:\program files\anaconda3\include\pyconfig.h(59): fatal error C1083: Cannot open include file: 'io.h': No such file or directory error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Community\\VC\\Tools\\MSVC\\14.10.25017\\bin\\HostX86\\x86\\cl.exe' failed with exit status 2

• I read the answer here . So I am trying to replace the path in my system environment like this: C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.10.25017\bin\HostX86\x86
  
  => C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.10.25017\bin\HostX86\x86
  
  but it does nothing for me.

• Then I try to load io.h
  
  and put in C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.10.25017\include
  
  , but it's no use.

• Finally I am trying to use conda install conda install -c conda-forge python-crfsuite
  
  and this is success

Question

• Why conda install
  
  doesn't the dose have a problem with io.h
  
  , any difference with pip install
  
  ?

• Why are there multiple cl.exe
  
  in different paths in VS (I'm not that familiar) and is there any difference in using different cl.exe
  
  ?

I am asking this question because even if I have installed Anaconda if I want to use pip install I have to face these problems and I still cannot figure it out