#02 – Encapsulation & Abstraction in Python

Welcome to Day 2! Today we focus on two core pillars of Object-Oriented Programming: Encapsulation: Hiding internal state and requiring all interaction to go through performing validation or controlled methods. Abstraction: Hiding complex implementation details and exposing only a clean, simplified interface to the user. 1. Access Modifiers: Public, Protected, & Private 🛡️ Python does not have strict enforcement keywords like public or private found in Java or C++. Instead, it uses naming conventions and name mangling to communicate intent and protect internal data. ┌─────────────────────────────────────────────────────────────────────────────┐ │ ACCESS MODIFIERS IN PYTHON │ ├──────────────┬───────────────┬──────────────────────────────────────────────┤ │ Level │ Syntax │ Scope / Intended Access │ ├──────────────┼───────────────┼──────────────────────────────────────────────┤ │ Public │ self.name │ Accessible anywhere (inside & outside class) │ │ Protected │ self._balance │ Internal & subclasses only (Convention) │ │ Private │ self.__pin │ Class internal only (Triggers Name Mangling) │ └──────────────┴───────────────┴──────────────────────────────────────────────┘ Public ( self.name ): Fully accessible from anywhere. Protected ( self._balance ): Single leading underscore. Signals to developers: "This is internal—do not mutate or access outside this class or its subclasses." Private ( self.__pin ): Double leading underscore. Triggers name mangling ( _ClassName__attribute ), making it hard to accidentally access or override outside the class. 💻 Code Example: Access Modifiers & Name Mangling class SecureVault : def __init__ ( self , owner : str , balance : float , pin_code : str ): self . owner = owner # Public self . _balance = balance # Protected (convention) self . __pin = pin_code # Private (name mangled) def verify_pin ( self , pin : str ) -> bool : return self . __pin == pin vault = SecureVault ( " Alice " , 50000.0 , " 9876 " ) # Public access works as expected