Unordered collections of unique items.
✍️ 3 exercises + code challenge in this lessonA set stores unique items with no order: tags = {"python", "web"}
add() or update(); remove with remove() or discard().| union, & intersection, - difference, ^ symmetric difference.set(). {} creates an empty dictionary.Mastering Python Sets helps you write clean and reliable Python code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
a = {"python", "sql", "html"}
b = {"html", "css", "javascript"}
print("Union:", a | b)
print("Both:", a & b)
print("Only in a:", a - b)
a.add("python") # duplicate: no change
a.add("git")
print(a)
print(len({1, 1, 2, 2, 3}))Check what you learned in “Python Sets”.
Create an empty set.
tags =
What happens when you add a duplicate to a set?
Print the items both sets have in common, sorted as a list.
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