[Lab-Deserialization-Pickle] Cannot read "/sauce" on webpage.

[Kaiserouo]

Upon clicking the link on page that is supposed to show source code, the server complains about the following message and loads nothing.

I can't find the problem myself, the main program looks very fine to me. Maybe the issue is in uwsgi but I already have the source code anyway, so I'll leave it to someone else to fix it for completeness sake.
Also, I don't know why but the cookies on other labs are carried to this page (maybe that's what happened), and since the cookie "session" is not a valid pickled message it showed internal server error. Adding advice to delete all cookies before doing this lab may be helpful to others doing it.

[Kaiserouo]

btw I don't really understand why I encountered so many problems while the lab in class works fine. Can you also label the environment you used for the server? e.g. OS, docker version, etc.
Don't know whether this would be helpful but I'll list my environment here anyway.