error: Unable to find vcvarsall.bat

The reason:
This error is almost inevitable for any Python extension installed that is closely related to the underlying operating system.
.bat files are batch files. Python requires third-party packages to be installed. These packages contain extension, sometimes called native modules, ending in. Pyd and containing platform-specific code. These packages may be written in other languages, so you need vcvarsall.bat to compile these modules. Vcvarsall.bat is a compiler for Visual Studio.
When installing a Python package, it is best to install it as a wheel, where the modules are already compiled. And PIP first downloads the WHEEL file. You can avoid these problems
Solutions:
“_MSvccompiler.py” is found in the python program folder in the virtual environment such as Anaconda

\Anaconda\envs\ENVNAME\Lib\distutils or \Anaconda\Lib\distutils

Find the “_find_vcvarsall” function declaration similar to “if version > = 14 and version > Best_version: “, pay attention to the “14” here. If it is 14, it means that the VS version should be above 14. So according to this sentence, we are going to install the latest Visual Studio2015. This error is due to my python3.6 and VS 2013. So you just need to install the corresponding version, or just Visual C++ Build Tools 2015. address
Reference:
https://github.com/mkleehammer/pyodbc/issues/77
https://stackoverflow.com/questions/28251314/error-microsoft-visual-c-10-0-is-required-unable-to-find-vcvarsall-bat

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