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Lesson 8 — Lists & Tuples Cheat Sheet

Python

In one line: Both lists and tuples store ordered sequences of items and support indexing, slicing, and for loops. The key difference is mutability: lists can be changed after creation; tuple...

Key Ideas

1Lists vs Tuples at a Glance. Both lists and tuples store ordered sequences of items and support indexing, slicing, and for loops. The key difference is mutability: lists can be changed after creat...

2Creating & Accessing Lists. A list is created with square brackets [ ]. Items can be of any type — even mixed types or other lists. Access items with an index (0-based), and use negative indexes ...

3Essential List Methods. Lists come with powerful built-in methods. These are called with dot notation: list.method(). Unlike string methods, most list methods modify the list in-place and ret...

4List Comprehensions. A list comprehension is Python's most elegant feature for creating lists. It collapses a loop-and-append pattern into a single, readable line. Once you learn it, you'l...

5Tuples — Immutable Sequences. Tuples are created with parentheses ( ) or just commas. They support indexing, slicing, and for loops exactly like lists — but you cannot add, remove, or change their ...

Code Examples

# Creating lists
fruits  = ["apple", "banana", "mango", "grape"]
marks   = [85, 92, 78, 95, 88]
mixed   = ["Ali", 21, True, 3.14]   # any types allowed
empty   = []                         # empty list
nested  = [[1,2], [3,4], [5,6]]   # list of lists

# In...

students = ["Ali", "Sara", "Zara"]

students.append("Omar")          # add to end
students.insert(1, "Bilal")      # insert at index 1
print(students)  # ['Ali', 'Bilal', 'Sara', 'Zara', 'Omar']

students.remove("Zara")          # remove by value
last = stu...

# Old way: loop + append
squares = []
for i in range(1, 6):
    squares.append(i ** 2)

# Comprehension — same result, one line
squares = [i ** 2 for i in range(1, 6)]
print(squares)     # [1, 4, 9, 16, 25]

# With a filter condition
evens  = [x for x in ra...