Object Oriented Programming - General Questions

Which module provides abstract base classes?

What is the output of the following code?

class T:
    def __init__(self):
        self.__secret = 1
t = T()
print(hasattr(t, '__secret'), hasattr(t, '_T__secret'))

What is the output of the following code?

class A:
    def hello(self):
        return 'A'
class B(A):
    def hello(self):
        return 'B' + super().hello()
print(B().hello())

What is the output of the following code?

class Animal:
    def sound(self):
        return 'generic'
class Cat(Animal):
    def sound(self):
        return 'meow'
print(Cat().sound(), Animal().sound())

What is the output of the following code?

class Temp:
    def __init__(self, c):
        self._c = c
    @property
    def f(self):
        return self._c * 9 / 5 + 32
print(Temp(100).f)