code: def fix_permissions (self):
          
          if os.name == 'posix' and not self.dry_run:
              # Make the data files we just installed world-readable,
              # and the directories world-executable as well.
              for path in self.get_outputs():
                  mode = os.stat(path)[stat.ST_MODE]
                  if stat.S_ISDIR(mode):
                      mode |= 0o11
                  mode |= 0o44
                  os.chmod(path, mode)
docs: Set correct read permissions on POSIX systems. Might also
          be possible by setting umask?