1. Why do we say that fastai has a “layered” API? What does it mean?
2. Why does a have a decode method? What does it do?
3. Why does a Transform have a setup method? What does it do?
4. How does a Transform work when called on a tuple?
5. Write a Normalize transform that fully normalizes items (subtract the mean and divide by the standard deviation of the dataset), and that can decode that behavior. Try not to peek!
6. Write a Transform that does the numericalization of tokenized texts (it should set its vocab automatically from the dataset seen and have a decode method). Look at the source code of fastai if you need help.
7. What is a ?
8. What is a TfmdLists?
9. What is a Datasets? How is it different from a TfmdLists?
10. How can you build a DataLoaders from a TfmdLists or a Datasets?
11. How do you pass and batch_tfms when building a DataLoaders from a TfmdLists or a Datasets?
12. What do you need to do when you want to have your custom items work with methods like show_batch or show_results?
13. Why can we easily apply fastai data augmentation transforms to the SiamesePair we built?

1. Use the mid-level API to prepare the data in DataLoaders on your own datasets. Try this with the Pet dataset and the Adult dataset from Chapter 1.