Section 2.5 ("Summary and Outlook") seems to be blank

[NeapolitanSuitcase]

I do not see any text or other content under "summary and outlook" in chapter 2 of the github etext. Does not seem intentional.

[wanghedy]

您的邮件已收到，我将会尽快处理，谢谢。王宇凝

[amueller]

There is no text in this repo, it is automatically generated from the book. So this is indeed "intentional".