# Python **1. Print Statement** ```python print("Hello, World!") ``` **2. Variables and Data Types** ```python age = 25 name = "John" is_student = True ``` **3. String Formatting** ```python greeting = f"Hello, {name}! You are {age} years old." ``` **4. Lists and Indexing** ```python my_list = [1, 2, 3, "four", 5.0] first_item = my_list[0] ``` **5. Dictionaries** ```python my_dict = {"key": "value", "name": "Alice"} value = my_dict["key"] ``` **6. Conditional Statements** ```python if age > 18: print("You are an adult.") elif age == 18: print("You just became an adult.") else: print("You are a minor.") ``` **7. Loops - For and While** ```python for i in range(5): print(i) counter = 0 while counter < 5: print(counter) counter += 1 ``` **8. Functions** ```python def greet(person): return f"Hello, {person}!" result = greet("Bob") ``` **9. List Comprehensions** ```python squared_numbers = [x**2 for x in range(5)] ``` **10. Exception Handling** ```python try: result = 10 / 0 except ZeroDivisionError: result = "Cannot divide by zero." ``` **11. Classes and Objects** ```python class Dog: def __init__(self, name): self.name = name my_dog = Dog("Buddy") ``` **12. File Handling** ```python with open("file.txt", "r") as file: content = file.read() ``` **13. Modules and Libraries** ```python import math sqrt_result = math.sqrt(25) ``` **14. Lambda Functions** ```python multiply = lambda x, y: x * y product = multiply(3, 4) ``` **15. Working with JSON** ```python import json data = '{"name": "John", "age": 25}' user_info = json.loads(data) ``` **16. Modules and Libraries** ```python import random random_number = random.randint(1, 10) ``` **17. Working with Files** ```python with open("new_file.txt", "w") as new_file: new_file.write("This is a new file.") ``` **18. Exception Handling (try, except, else, finally)** ```python try: result = 10 / 2 except ZeroDivisionError: result = "Cannot divide by zero." else: print(f"Result: {result}") finally: print("Execution complete.") ``` **19. Classes and Inheritance** ```python class Animal: def speak(self): return "Some generic sound." class Dog(Animal): def speak(self): return "Woof!" my_animal = Animal() my_dog = Dog() animal_sound = my_animal.speak() dog_sound = my_dog.speak() ``` **20. List Manipulation** ```python numbers = [1, 2, 3, 4, 5] numbers.append(6) numbers.pop(2) ``` **21. Sets** ```python my_set = {1, 2, 3, 4, 5} my_set.add(6) ``` **22. Tuples** ```python coordinates = (3, 4) x, y = coordinates ``` **23. Working with Dates and Times** ```python from datetime import datetime current_time = datetime.now() formatted_time = current_time.strftime("%Y-%m-%d %H:%M:%S") ``` **24. List Sorting** ```python numbers = [4, 2, 7, 1, 9] sorted_numbers = sorted(numbers) ``` **25. Map, Filter, and Reduce** ```python numbers = [1, 2, 3, 4, 5] squared_numbers = list(map(lambda x: x**2, numbers)) even_numbers = list(filter(lambda x: x % 2 == 0, numbers)) sum_of_numbers = functools.reduce(lambda x, y: x + y, numbers) ``` **26. Virtual Environments** ```bash # Create virtual environment python -m venv myenv # Activate virtual environment source myenv/bin/activate # On Linux/Mac myenv\Scripts\activate # On Windows # Deactivate virtual environment deactivate ``` **27. Working with APIs** ```python import requests response = requests.get("https://jsonplaceholder.typicode.com/todos/1") data = response.json() ``` **28. Regular Expressions** ```python import re pattern = re.compile(r'\b(\w+)\b') matches = pattern.findall("This is a sample sentence.") ``` **29. Lambda Functions** ```python square = lambda x: x**2 result = square(5) ``` **30. List Comprehensions** ```python squares = [x**2 for x in range(5)] ``` **31. Dictionary Manipulation** ```python my_dict = {'a': 1, 'b': 2, 'c': 3} my_dict['d'] = 4 del my_dict['b'] ``` **32. JSON Manipulation** ```python import json # Convert Python object to JSON string json_data = json.dumps({'name': 'John', 'age': 30}) # Convert JSON string to Python object python_object = json.loads('{"name": "John", "age": 30}') ``` **33. Context Managers** ```python with open('file.txt', 'r') as file: content = file.read() # File is automatically closed outside the block ``` **34. Decorators** ```python 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() ``` **35. Asyncio (Asynchronous Programming)** ```python import asyncio async def my_coroutine(): print("Coroutine started.") await asyncio.sleep(1) print("Coroutine completed.") # Run the coroutine asyncio.run(my_coroutine()) ``` **36. Web Scraping with BeautifulSoup** ```python from bs4 import BeautifulSoup import requests url = "https://example.com" response = requests.get(url) soup = BeautifulSoup(response.text, 'html.parser') ``` **37. Machine Learning with Scikit-Learn** ```python from sklearn.model_selection import train_test_split from sklearn.linear_model import LinearRegression # Assuming X and y are your features and target variable X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2) model = LinearRegression() model.fit(X_train, y_train) ``` **38. Django Web Framework** ```bash # Install Django pip install Django # Create a new Django project django-admin startproject myproject # Run the development server python manage.py runserver ``` **39. Flask Web Framework** ```python from flask import Flask app = Flask(__name__) @app.route('/') def hello_world(): return 'Hello, World!' ``` **40. Creating a Simple REST API with Flask-RESTful** ```python from flask import Flask from flask_restful import Resource, Api app = Flask(__name__) api = Api(app) class HelloWorld(Resource): def get(self): return {'hello': 'world'} api.add_resource(HelloWorld, '/') ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://sallam.gitbook.io/sec-88/programming/python.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. 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