Ex42, confused between Object & Class in Python

Python
#1

Hi all,

I am reading ex42. Before this ex 42. I was thinking of defining a class as below

class Animal(object):
    pass

Animal is the class name. And when you say cat=Animal(), you define an object cat using the class Animal.

But ex42 told me that

You use the phrase is-a when you talk about objects and classes being related to each other by a class relationship.

and

## Animal is-a object (yes, sort of confusing) look at the extra credit
class Animal(object):
    pass

Here, animal seems a less abstract concept and object is the more abstract one. If I understand correctly, class is an abstraction of a type of objects. However, this is not consistent with the book.

Maybe I get things wrong. Can someone help to clarify? Thank you!

#2

No that’s right. “object” is very generic, “Animal” is slightly generic, “Salmon” is less generic, and this is very specific:

jonas = Salmon()

That would make a specific instance of salmon.

#3

I think I get a bit now.

you can define a class from more generic classes as well, right?

Like Dog and Cat are derived from the class Animal.

#4

Yes, that’s actually the only thing you can do. You can’t really “define” a generic class from a specific one.