Understanding Python Sets: A Beginner’s Guide

A set is a collection of unique, unordered elements. It does not allow duplicates. Lists are mutable (can be changed), whereas tuples are immutable (cannot be changed). Sets, like lists and tuples, are heterogeneous but do not allow duplicates.

You can create a set with curly braces, but an empty set is created with the set() function, as curly braces for an empty set represent a dictionary.
Example: set1 = {1, 2, 3, 4}, empty_set = set().

Sets do not allow duplicate elements, and Python automatically removes duplicates when adding to a set.

The add() method is used to add elements to a set.

You can use the discard() method to remove an element without raising an error if the element does not exist.

discard() does not raise an error if the element is not found, whereas remove() raises an error if the element is not present.

issubset() checks if all elements of one set are present in another set, returning True or False.

Sets are unordered, meaning that their elements do not have a defined order, and this order can change when printed or iterated over.

Sets cannot contain mutable elements like lists because mutable objects are not hashable, and sets require elements to be hashable and immutable.

Spaced Repetition Schedule:

Immediate Review (in 1 hour): Review differences between lists, tuples, and sets to clarify immutability and heterogeneity.
Next Day Review: Go over methods like add(), discard(), and remove() to reinforce their usage.
3 Days Before Test: Review everything, focusing on set operations like union, intersection, and subset methods.
Day Before Test: Do a quick revision, especially the tricky points like why sets don't allow mutable elements.

Set Datatype Quiz:

What is a Python set, and how is it different from lists or tuples?
How do you create a set in Python? Provide an example.
Can a Python set contain duplicate elements? Why or why not?
What is the method to add an element to a set?
How can you remove an element from a set without raising an error if the element doesn't exist?
What is the difference between discard() and remove() methods in sets?
How do you perform set union and intersection in Python?
What does the issubset() method do?
Are Python sets ordered or unordered?
Can a set contain mutable elements like lists? Explain why.