Book Image

Python Fundamentals

By : Ryan Marvin, Mark Ng’ang’a, Amos Omondi
Book Image

Python Fundamentals

By: Ryan Marvin, Mark Ng’ang’a, Amos Omondi

Overview of this book

<p>After a brief history of Python and key differences between Python 2 and Python 3, you'll understand how Python has been used in applications such as YouTube and Google App Engine. As you work with the language, you'll learn about control statements, delve into controlling program flow and gradually work on more structured programs via functions.</p> <p>As you settle into the Python ecosystem, you'll learn about data structures and study ways to correctly store and represent information. By working through specific examples, you'll learn how Python implements object-oriented programming (OOP) concepts of abstraction, encapsulation of data, inheritance, and polymorphism. You'll be given an overview of how imports, modules, and packages work in Python, how you can handle errors to prevent apps from crashing, as well as file manipulation.</p> <p>By the end of this book, you'll have built up an impressive portfolio of projects and armed yourself with the skills you need to tackle Python projects in the real world.</p>
Table of Contents (12 chapters)
Python Fundamentals
Preface

Chapter 9: Error Handling


Activity 39: Identifying Error Scenarios

Solution:

KeyError:

building = dict(
    name="XYZ Towers",
    type="Business Premises"
)
print(f"I went to visit {building['name']} yesterday at {building['street']}.")

AttributeError:

import string letters = string.asciiletters

Activity 40: Handling Errors

Solution:

import random

try:
    print(random.randinteger(1,10))
except AttributeError:
    print("Oops! Something went wrong")

Activity 41: Creating Your Own Custom Exception Class

Solution:

class RecipeNotValidError(Exception):
    def __init__(self):
        self.message = "Your recipe is not valid"

try:
    raise RecipeNotValidError
except RecipeNotValidError as e:
    print(e.message)