Lesson 6: Lists, Tuples, and Dictionaries | Coding Class Series
Introduction
Welcome to Lesson 6!
In this lesson, we will learn about Python data structures: lists, tuples, and dictionaries. These structures help you store and organize multiple values efficiently.
1. Lists
A list is an ordered and mutable collection of items.
You can add, remove, or change elements in a list.
Syntax:
fruits = ["apple", "banana", "cherry"]
print(fruits[0]) # Access first item
Common List Methods:
fruits.append("orange") # Add item
fruits.remove("banana") # Remove item
fruits.sort() # Sort items
print(fruits)
2. Tuples
A tuple is ordered but immutable.
Once created, you cannot change its elements.
Syntax:
coordinates = (10, 20)
print(coordinates[0])
Why use tuples?
- They are faster than lists
- Useful for data that should not change, like coordinates or constants.
3. Dictionaries
A dictionary stores key-value pairs.
You can access values using keys, not indexes.
Syntax:
student = {"name": "Alice", "age": 16, "grade": "A"}
print(student["name"]) # Output: Alice
Common Dictionary Methods:
student["age"] = 17 # Update value
student["city"] = "Delhi" # Add new key-value pair
print(student.keys()) # Show all keys
print(student.values()) # Show all values
Practice Exercises
- Create a list of your 5 favorite movies. Print them in alphabetical order.
- Create a tuple of your 3 favorite colors and try to change one color (observe what happens).
- Create a dictionary for a book:
title,author,year. Update theyearand print all keys and values. - Use a list of dictionaries to store 3 students’ information and print each student’s name and grade.
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