In the “what changed list”, 3rd bullet point says:

The section [project.entry-points.“pytest-11”] is added […]

However, the code example above shows this section as [project.entry-points."pytest11"] (no dash between pytest and 11). Searching the pytest documentation referenced by the book, it appears that the code is correct and the bullet point needs changing (i.e. remove the dash).

Second typo on page 208, after the list:

Check out the Flit documentation for a good write-up of all you can put in pyprojec.toml.

This should be pyproject.toml.