Python Sets
Sets are used to store multiple items in a single variable. A set is a collection which is unordered, unchangeable*, and unindexed.
Note: Set items are unchangeable, but you can remove items and add new items.
Creating a Set
Sets are written with curly brackets.
thisset = {"apple", "banana", "cherry"}
print(thisset)Access Items
You cannot access items in a set by referring to an index or a key. However, you can loop through the set items using a for loop, or ask if a specified value is present in a set, by using the in keyword.
thisset = {"apple", "banana", "cherry"}
for x in thisset:
print(x)
print("banana" in thisset) # Output: TrueAdd Items
To add one item to a set use the add() method.
thisset.add("orange")To add items from another set into the current set, use the update() method.
tropical = {"pineapple", "mango", "papaya"}
thisset.update(tropical)Remove Items
To remove an item in a set, use the remove(), or the discard() method.
thisset.remove("banana")
thisset.discard("banana")Set Operations
Union
The union() method returns a new set with all items from both sets.
set1 = {"a", "b" , "c"}
set2 = {1, 2, 3}
set3 = set1.union(set2)
print(set3)