code: def _guess_vc(self):
          
          if self.vc_ver <= 14.0:
              return
  
          default = r'VC\Tools\MSVC'
          guess_vc = os.path.join(self.VSInstallDir, default)
          # Subdir with VC exact version as name
          try:
              vc_exact_ver = os.listdir(guess_vc)[-1]
              return os.path.join(guess_vc, vc_exact_ver)
          except (OSError, IOError, IndexError):
              pass
docs: Locate Visual C for 2017