docs: def symlink(target, link):
      """os.symlink() but use a junction point on Windows.
      """
      if islink(link):
          unlink(link)
      if platform.system() == "Windows":
          if sys.version_info[:2] < (3, 5):
              with open(os.devnull, "w") as nul:
                  subprocess.check_call(["mklink", "/J", link, target], shell=True, stdout=nul)
          else:
              _winapi.CreateJunction(target, link)
      else:
          os.symlink(target, link)