Given these two classes, what do the following lines evaluate to?

class Owner(object):
    all = []

    def __init__(self, name):
        self.name = name
        self.pets = []
        Owner.all.append(self)

    def add_pet(self, pet):
        self.pets.append(pet)

    def __repr__(self):
        return 'Owner(' + self.name + ')'

class Pet(object):
    all = []

    def __init__(self, name, weight, height):
        self.name = name
        self.weight = weight
        self.height = height
        Pet.all.append(self)

    @property
    def bmi(self):
        return self.weight / (self.height * self.height)

    def __repr__(self):
        return 'Pet(' + self.name + ')'

>>> bob = Owner('bob')
>>> joe = Owner('joe')
>>> bob.all                 #1

>>> bob.all.append(bob)
>>> joe.all                 #2

>>> type(joe.add_pet)       #3

>>> type(Owner.add_pet)     #4

>>> harry = Pet('harry', 50, 50)
>>> type(harry.bmi)         #5

>>> joe.pets.append(harry)
>>> bob.add_pet(harry)
>>> bob.pets[0].all         #6

>>> bob.pets.append(Pet('jimmy', 40, 10))
>>> bob.pets[1].owner       #7

>>> Pet.all                 #8

>>> jimmy                   #9

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