In chapter 02, it's stated that the classical mapping is an alternative to the declarative mapping and that:

This gives us all the benefits of SQLAlchemy

See here: https://github.com/cosmicpython/book/blob/master/chapter_02_repository.asciidoc#inverting-the-dependency-orm-depends-on-model

But, in the SQLAlchemy documentation about Imperative/Classical Mapping, the following is stated:

The imperative mapping form is a lesser-used form of mapping that originates from the very first releases of SQLAlchemy in 2006. It’s essentially a means of bypassing the Declarative system to provide a more "barebones" system of mapping, and does not offer modern features such as PEP 484 support. As such, most documentation examples use Declarative forms, and it’s recommended that new users start with Declarative Table configuration.

(Emphasis mine)

The content of this chapter should probably be modified to indicate that.
Also, is there an alternative that would use the recommended Declarative mapping?