OOPs

1. Class and Object A class is a blueprint for creating objects. It defines a set of attributes and methods that the objects of that class will have. class Dog: def __init__(self, name, breed): self.name = name self.breed = breed def bark(self): return f"{self.name} says Woof!" # Creating an object my_dog = Dog("Buddy", "Golden Retriever") print(my_dog.bark()) # Output: Buddy says Woof! Illustration: Class (Dog) +-------------------+ | Attributes | | - name | | - breed | | | | Methods | | - bark() | +-------------------+ ^ | | Instance | +-------------------+ | Object (my_dog) | | name: Buddy | | breed: Golden | | Retriever | +-------------------+ 2....

1. Property Decorators Properties allow you to use methods like attributes, providing a clean way to implement getters, setters, and deleters. class Temperature: def __init__(self, celsius): self._celsius = celsius @property def celsius(self): return self._celsius @celsius.setter def celsius(self, value): if value < -273.15: raise ValueError("Temperature below absolute zero is not possible") self._celsius = value @property def fahrenheit(self): return (self.celsius * 9/5) + 32 @fahrenheit.setter def fahrenheit(self, value): self.celsius = (value - 32) * 5/9 temp = Temperature(25) print(temp....

1. Database Connection Pool using Singleton and Context Manager Problem: Managing database connections efficiently in a multi-threaded application. Solution: Use the Singleton pattern to ensure a single connection pool, and a context manager for safe connection handling. import threading from contextlib import contextmanager class DatabasePool: _instance = None _lock = threading.Lock() def __new__(cls): if cls._instance is None: with cls._lock: if cls._instance is None: cls._instance = super().__new__(cls) cls._instance.connections = [] return cls....