This document discusses the sort() function in Python for sorting lists. It explains that sort() sorts lists in place by default and can sort complex objects like dictionaries and tuples by specifying a key function. The key parameter allows sorting by a specific key or value. The document provides examples of sorting lists of dictionaries by age and tuples by a value, as well as explaining the differences between in-place and non-in-place sorting methods.

1. Sort() Function in
Python Unlocking
the Power of
Sorting Lists
AM – MAY 2023

2. Outline
 Basic Usage
 Sorting by Key
 Sorting Complex Object
 In-Place vs Non-In-Place Sorting

3. sort(key=None, reverse=False)
“This method sorts the list in place, using
only < comparisons between items. Exceptions are not
suppressed - if any comparison operations fail, the
entire sort operation will fail (and the list will
likely be left in a partially modified state)”
-https://docs.python.org-
Parameter Description
Reverse
Optional. reverse=True will sort the list descending. Default is
reverse=False
Key Optional. A function to specify the sorting criteria(s)
Source: https://www.w3schools.com

4. Basic Usage
The sort() function is used to sort a list in ascending or
descending order.

5. Sorting by Key
A key is a function that takes an element in the list as
an argument and returns a value that is used for sorting

6. Sorting Complex Object
The sort() function can also be used to sort complex
objects, such as dictionaries and tuples, by specifying a
key function
# Sorting a list of dictionaries by a specific key
people = [{"name": "Alice", "age": 25}, {"name": "Bob", "age": 18}, {"name": "Charlie", "age": 32}]
people.sort(key=lambda x: x["age"])
print(people) # Output: [{'name': 'Bob', 'age': 18}, {'name': 'Alice', 'age': 25}, {'name': 'Charlie',
'age': 32}]
# Sorting a list of tuples by a specific value
inventory = [("apple", 10), ("banana", 5), ("orange", 7)]
inventory.sort(key=lambda x: x[1], reverse=True)
print(inventory) # Output: [('apple', 10), ('orange', 7), ('banana', 5)]

7. In-Place vs Non-In-Place Sorting
► In-place sorting: Modifies the original list
► Non-in-place sorting: Returns a new sorted list

8. Sort() Function in
Python Unlocking
the Power of
Sorting Lists
AM – MAY 2023