human
I am working on the file "Day_02/01_ObjectOrientedProgramming/00_Object_Oriented_Programming.ipynb".
The first task is:
In this example, we have two classes: Animal and Dog. The Animal is the base class, the Dog is the derived class. The derived class inherits the functionality of the base class. It is shown by the eat() method. The derived class modifies existing behaviour of the base class, shown by the whoAmI() method. Finally, the derived class extends the functionality of the base class, by defining a new bark() method. 
We put the ancestor classes in round brackets after the name of the descendant class. If the derived class provides its own __init__() method, it must explicitly call the base class __init__() method. 
Polymorphism
The polymorphism is the process of using an operator or function in different ways for different data input. In practical terms, polymorphism means that if class B inherits from class A, it doesn’t have to inherit everything about class A.
it can do some of the things that class A does differently.
Can you write Python program for it?
 ... What is a the Python program you requested?
assistant
#Here is the Python program you requested.

class Animal:
   def __init__(self, name=''):
      self.name = name

   def talk(self):
      pass

class Cat(Animal):
   def talk(self):
      print "Meow!"

class Dog(Animal):
   def talk(self):
      print "Woof!"

a = Animal()
a.talk()

c = Cat("Missy")
c.talk()

d = Dog("Rocky")
d.talk()