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Sets Quiz

Sets are like Lists, but they are unordered and they guarantee uniqueness. Only ONE of each value can be in a set.

fruits = {"apple", "banana", "grape"}
print(type(fruits))
# Prints: <class 'set'>

print(fruits)
# Prints: {'banana', 'grape', 'apple'}

Add Values

You can .add() values to a set. Think of .add() like append but for sets!

fruits = {"apple", "banana", "grape"}
fruits.add("pear")
print(fruits)
# Prints: {'pear', 'banana', 'grape', 'apple'}

No error will be raised if you add an item already in the set, and the set will remain unchanged.

Because the empty bracket {} syntax creates an empty dictionary, to create an empty set, you need to use the set() function.

fruits = set()
fruits.add("pear")
print(fruits)
# Prints: {'pear'}

fruits = {"apple", "banana", "grape"}
for fruit in fruits:
    print(fruit)
    # Prints:
    # banana
    # grape
    # apple

Note: Sets are unordered, so the order of iteration is not guaranteed.

fruits = {"apple", "banana", "grape"}
fruits.remove("apple")
print(fruits)
# Prints: {'banana', 'grape'}