book-programming-phoenix-liveview: Errors in Chapter 3

Title: Programming Phoenix LiveViw: v1.0 (page 84)
Example: Version mismatches in Chapter 3

There numerous mismatches between instructions, data & generators. This is throught the chapter, some examples are:
When displaying help for the product context the book shows a function changeset/2 but after following the instructions there is no changeset/2 there is a changeset/3 wich includes a user_scope parameter but that is never passed in the Test Drive the Schema section. In fact I have not found any direct refernce to this parameter in the chapter so far. I understand what this is for but it seems like parts of this chapter are from earlier versions.