Python Basics: Variables, Control Flow, Data Structures, and Object‑Oriented Programming

Python is a high‑level programming language designed for code readability, allowing developers to express ideas with minimal syntax; it is widely used in data science, web development, and machine learning.

Variables are created by simple assignment, for example one = 1 , two = 2 , some_number = 10000 . Python supports integers, booleans, strings, floats, and other data types.

Control flow uses if , elif , and else statements to execute code based on conditions, e.g. if True: print("Hello Python If") if 2 > 1: print("2 is greater than 1") else: print("1 is not greater than 2")

Loops enable repeated execution. A while loop runs while a condition is true: num = 1 while num <= 10: print(num) num += 1 . A for loop iterates over a range or a collection, e.g. for i in range(1, 11): print(i) .

Lists store ordered collections of items. They are created with square brackets, indexed from zero, and can be extended with append . my_integers = [1, 2, 3, 4, 5] bookshelf = [] bookshelf.append("The Effective Engineer") print(bookshelf[0])

Dictionaries hold key‑value pairs. Access values via their keys and iterate over items. dictionary_tk = {"name": "Leandro", "nickname": "Tk", "nationality": "Brazilian"} print(dictionary_tk["name"]) # Leandro

Object‑oriented programming defines classes as blueprints. The __init__ method initializes attributes, and methods implement behavior. Example of a simple class with getters and setters using @property : class Vehicle: def __init__(self, wheels, tank, seats, max_speed): self.number_of_wheels = wheels self.type_of_tank = tank self.seating_capacity = seats self.maximum_velocity = max_speed @property def number_of_wheels(self): return self._wheels @number_of_wheels.setter def number_of_wheels(self, value): self._wheels = value

Encapsulation hides internal state. Public attributes are accessed directly, while non‑public attributes use a leading underscore and are manipulated through methods. class Person: def __init__(self, first_name, email): self.first_name = first_name self._email = email def email(self): return self._email def update_email(self, new_email): self._email = new_email

Inheritance allows a subclass to reuse and extend a parent class. An ElectricCar can inherit from Car without redefining shared attributes: class Car: def __init__(self, wheels, seats, max_speed): self.number_of_wheels = wheels self.seating_capacity = seats self.maximum_velocity = max_speed class ElectricCar(Car): def __init__(self, wheels, seats, max_speed): super().__init__(wheels, seats, max_speed)

The tutorial covers these core Python concepts, providing clear explanations and runnable code snippets to help beginners build a solid foundation in the language.