docs: def posixpath_normpath(pathname):
      """
      Convert path into POSIX path:
  
        * Normalize path
        * Replace backslash with slash
  
      :param pathname: Pathname (as string)
      :return: Normalized POSIX path.
      """
      backslash = '\\'
      pathname2 = os.path.normpath(pathname) or "."
      if backslash in pathname2:
          pathname2 = pathname2.replace(backslash, '/')
      return pathname2