How to get information from fastai objects?

Greetings, fellow fastai learners!

Been trying for days to find out how to extract information from objects created by the fastai library, but they seem to be impenetrable black boxes. Using the ?? prefix to the object to get documentation doesn’t provide the needed info.

Then, in Unofficial Deep Learning Lecture 2 Notes, I found the line

data.trn_ds.fnames[0],

which extracts the first filename from the training data set in the Kaggle Dog Breed Classification Challenge. Here, data is an ImageClassifierData object.

This is great! But I had no idea that ImageClassifierData objects have the property ‘.trn_ds.fnames’! How could I have known?

More specifically, question is:

"How can we find out what information is available to be extracted from an ImageClassifierData object, or in general, any object created by fastai libraries?"

Is there a syntax for manipulating these objects – ie, finding out their methods and properties and how to invoke them?

Any help will be much appreciated!

Cheers,
jcatanza

I am hoping that someone replies to this question.