Sorry Sara – I discovered it was my error after I began the question. If possible, please delete the question.
Don’t worry. I’ll close this issue.
Anyway, if you find any typos or issues, please let us know.
There is an errata on the eBook page: https://rntlab.com/module-1/welcome-build-web-servers/
A new version of the eBook will be released during the month of February with fixed typos and 7 new projects. You’ll be notified via email.