Python - Lists & Tuples

Overview

Estimated time: 30–40 minutes

Work with lists and tuples: creation, indexing, slicing, methods, and when to choose one over the other.

Learning Objectives

• Create and manipulate lists and tuples safely.
• Use slicing effectively to copy or extract subsequences.
• Decide when immutability (tuples) is beneficial.

Prerequisites

• Python - Functions Basics

Lists

nums = [10, 20, 30]
nums.append(40)
print(nums[1])
print(nums[:2])

Expected Output: 20\n[10, 20]

Tuples

pt = (3, 4)
print(len(pt))
# pt[0] = 5  # TypeError: immutable

Expected Output: 2

Common Pitfalls

• Confusing shallow copy via slicing vs deep copy for nested lists.
• Trying to modify a tuple (immutable); use a list if mutation is needed.

Checks for Understanding

1. How do you copy a list?
2. When would you prefer a tuple to a list?

Exercises

1. Slice a list to get the last two elements.
2. Unpack a tuple (x, y) and print a formatted string.