docs: def log_analyzer(path):
      """This procedure replaces every line which can't be parsed
      with special object MalformedLogEntry.
      """
      with handle(MalformedLogEntryError,
                    lambda (c):
                        invoke_restart('use_value',
                                       MalformedLogEntry(c.text))):
          for filename in find_all_logs(path):
              analyze_log(filename)