is recipe book is special because it's not just any old collection of recipes. It's been carefully curated to include only the best, most instructive recipes (the filtered code-language dataset), and it also includes some brand new, innovative recipes created by another top chef (the synthetic textbook dataset). 

By learning from this high-quality recipe book, the chef is able to cook up some impressive dishes (generate high-quality code), despite working in a smaller kitchen. 

So, the bottom line is that