add Escape charcters in string

[ibreeden]

And two more solutions:

1. Make it a raw string by prepending "r". In raw strings a backlslash will not be interpreted.
   cmd = r"C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\Common7\IDE\CommonExtensions\Microsoft\TestWindow\vstest.console.exe"
   
2. Use forward slashes instead of backslashes. Python will understand this.