[BUG] Chapter 4 - the regularization lack of data in the book

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**Describe the bug**
Hi, on Chapter 4 - page 156 and 157 of the book the new X and y are not defined which makes the fit result different from the book
they are defined in the Colab of the book but as extra code.

**Screenshots**
If applicable, add screenshots to help explain your problem.
this is the result if we go through the path of the book:
This is the part in Colab defining the new X and y
which result in these answers :

Thanks for the helpful and great book of yours:)