Python #4

In this session, we'll explore more advanced topics in Python programming, including object-oriented programming (OOP) concepts, decorators, and an introduction to handling data with APIs.

Advanced Object-Oriented Programming

Inheritance

Inheritance allows one class to inherit attributes and methods from another class.

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

    def speak(self):
        pass

class Dog(Animal):
    def speak(self):
        return "Woof!"

class Cat(Animal):
    def speak(self):
        return "Meow!"

dog = Dog("Buddy")
cat = Cat("Whiskers")
print(dog.speak())  # Output: Woof!
print(cat.speak())  # Output: Meow!

Polymorphism

Polymorphism allows methods to be used in different ways for different objects.

animals = [Dog("Buddy"), Cat("Whiskers")]

for animal in animals:
    print(animal.speak())

Decorators

Decorators are a way to modify the behavior of functions or methods. They are often used for logging, access control, or modifying input/output.

def my_decorator(func):
    def wrapper():
        print("Something is happening before the function is called.")
        func()
        print("Something is happening after the function is called.")
    return wrapper

@my_decorator
def say_hello():
    print("Hello!")

say_hello()

Working with APIs

APIs (Application Programming Interfaces) allow you to interact with external services. Python's requests library is commonly used to make HTTP requests.

Making a GET Request

import requests

response = requests.get('https://api.example.com/data')
if response.status_code == 200:
    data = response.json()
    print(data)
else:
    print("Failed to retrieve data")

Making a POST Request

payload = {'key1': 'value1', 'key2': 'value2'}
response = requests.post('https://api.example.com/data', json=payload)
if response.status_code == 201:
    print("Data posted successfully")
else:
    print("Failed to post data")

Handling JSON Data

JSON (JavaScript Object Notation) is a common format for data exchange. Python provides the json module for working with JSON data.

Parsing JSON

import json

json_data = '{"name": "Alice", "age": 25}'
data = json.loads(json_data)
print(data['name'])  # Output: Alice

Creating JSON

data = {'name': 'Alice', 'age': 25}
json_data = json.dumps(data)
print(json_data)  # Output: {"name": "Alice", "age": 25}

These advanced topics will help you build more sophisticated and efficient Python applications, especially when dealing with larger codebases or integrating with external systems.