EX Exercises

Task

In this exercise, you will model an animal using object-oriented programming
and determine its typical region and sleep behavior based on predefined data.

The goal is to understand how:

  • objects use internal data
  • methods make decisions
  • shared data belongs to a class, not to individual objects

Step 1: Create the class

Create a class named Animal.

Step 2: Define the attributes

Each animal object should have:

  • name — the name of the animal
  • age — the age of the animal

These values are specific to each object.

Step 3: Define shared data (class variables)

Inside the class, define two class-level data structures.

Animal regions

animal_regions = [
    ["Lion", "Africa"],
    ["Elephant", "Africa"],
    ["Polar Bear", "Arctic"],
    ["Penguin", "Antarctica"],
    ["Kangaroo", "Australia"]
]

Animal sleep duration

Define a second list that stores how long an animal typically sleeps per day
(in hours).

animal_sleep = [
    ["Lion", 20],
    ["Elephant", 4],
    ["Polar Bear", 8],
    ["Penguin", 12],
    ["Kangaroo", 15]
]

Both lists represent shared knowledge:

  • they belong to the class
  • all objects can access them
  • they should not be passed as parameters

Step 4: Define the methods

region()

  • This method takes no parameters (except self)
  • It uses self.name to look up the animal in animal_regions
  • It prints the corresponding region
  • If the animal is not found, it prints a default message

sleep()

  • This method takes no parameters (except self)
  • It uses self.name to look up the animal in animal_sleep
  • It prints how many hours the animal typically sleeps per day
  • If the animal is not found, it prints a default message

Example output:

  • "The lion sleeps about 20 hours per day."
  • "Sleep information for this animal is unknown."

Step 5: Constructor

Define a constructor (__init__) that initializes:

  • name
  • age

Use self to store these values.

Step 6: Create and test objects

  • Create one or more animals
  • Call region() and sleep()
  • Observe how both methods determine information automatically
    based on class-level data

Example structure (no full solution)

class Animal:
    animal_regions = [
        ["Lion", "Africa"],
        ["Polar Bear", "Arctic"]
    ]

    animal_sleep = [
        ["Lion", 20],
        ["Polar Bear", 8]
    ]

    def __init__(self, name, age):
        self.name = name
        self.age = age

    def region(self):
        # search for self.name in animal_regions
        pass

    def sleep(self):
        # search for self.name in animal_sleep
        pass

Hint

  • Use a loop to search through the lists
  • Compare the stored name with self.name
  • Do not add parameters to region() or sleep()
  • Focus on clarity and logical structure

This exercise demonstrates how multiple class variables
can be used to describe different aspects of object behavior.

Updated: