add topic - OOPs for python

Author: Seema Kumari Patel

docs/python/python_oops.md

@@ -0,0 +1,120 @@
+#author: seema kumari patel
+#OOPs concept - Python
+
+---
+id: python-OOPs
+title: Python OOPs concept
+sidebar_label: Python OOPs concept #displays in sidebar
+sidebar_position: 19
+tags:
+  [
+    Python,
+    Introduction of python,
+    Python Syntax,
+    Python Variables,
+     Python Operators,
+
+  ]
+
+---
+
+
+# Python OOPs
+
+**OOP** is a way of organizing code that uses objects and classes to represent real-world entities and their behavior. In OOP, object has attributes thing that has specific data and can perform certain actions using methods.
+
+
+Characteristics of OOP (Object Oriented Programming)
+Python supports the core principles of object-oriented programming, which are the building blocks for designing robust and reusable software. The diagram below demonstrates these core principles:
+
+1. Class - A blueprint for creating objects.
+
+📌 **Use Case**: create a class - car
+
+class Car:
+    def __init__(self, brand, model):
+        self.brand = brand
+        self.model = model
+
+    def start(self):
+        print(f"{self.brand} {self.model} is starting...")
+
+2. Object - An instance of a class.
+
+📌 **Use Case**: instantiate the variables
+
+my_car = Car("Tesla", "Model S")
+my_car.start()  # Tesla Model S is starting...
+
+
+3. Encapsulation - Hiding the internal details and only exposing necessary parts.
+
+📌 **Use Case**: Not letting data to be accessed by other class
+
+class BankAccount:
+    def __init__(self, balance):
+        self.__balance = balance  # private variable
+
+    def deposit(self, amount):
+        self.__balance += amount
+
+    def get_balance(self):
+        return self.__balance
+
+
+4. Inheritance - One class can inherit from another.
+
+📌 **Use Case**: car (parent) class is getting inherited by (child) ElectricCar
+
+class ElectricCar(Car):
+    def __init__(self, brand, model, battery):
+        super().__init__(brand, model)
+        self.battery = battery
+
+    def battery_info(self):
+        print(f"Battery: {self.battery} kWh")
+
+tesla = ElectricCar("Tesla", "Model X", 100)
+tesla.start()
+tesla.battery_info()
+
+
+5. Polymorphism - Same function name, but different behavior depending on the object.
+
+📌 **Use Case**: Different classes using single method for different purposes.
+
+class Dog:
+    def speak(self):
+        return "Woof!"
+
+class Cat:
+    def speak(self):
+        return "Meow!"
+
+pets = [Dog(), Cat()]
+for pet in pets:
+    print(pet.speak())  # Woof! / Meow!
+
+
+6. Abstraction - Hiding implementation details, showing only essential features (using abc module).
+
+📌 **Use Case**: Hiding low level details
+
+from abc import ABC, abstractmethod
+
+class Shape(ABC):
+    @abstractmethod
+    def area(self):
+        pass
+
+class Circle(Shape):
+    def __init__(self, radius):
+        self.radius = radius
+
+    def area(self):
+        return 3.14 * self.radius ** 2
+
+c = Circle(5)
+print(c.area())  # 78.5
+
+