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Sets
Set Operations: .union()

Another set operation we can use is `.union()`. This operation creates a set by combining the values of two sets together.

The syntax for creating a set using `.union()` is:

``var NewSet = SetA.union(SetB)``

Consider the following sets `book1` and `book2` that contain the characters of different fairy tales:

``````var book1: Set = ["Pig 1", "Pig 2", "Pig 3", "Wolf"]

var book2: Set = ["Little Red Riding Hood", "Grandma", "Wolf"]``````

We can use `.union()` to combine all the characters into one set called `fairyTales`:

``var fairyTales = book1.union(book2)``

Imagine finding a third book, `book3`:

``var book3: Set = ["Jack", "Blunderbore", "Beanstock"]``

With set operations, we can combine multiple sets like this:

``var fairyTales = book1.union(book2).union(book3)``

Using multiple methods in the same line of code is known as method chaining.

When we print `fairyTales`, we will get something similar to the following output:

``["Blunderbore", "Pig 1", "Pig 2", "Little Red Riding Hood", "Pig 3", "Grandma", "Wolf", "Jack", "Beanstock"]``

The element `"Wolf"` appeared in both `book1` and `book2`; however, the element only appears once in `fairyTales` because sets only contain unique elements.

### Instructions

1.

In Alphabet.swift, create a set called `alphabet` that uses `.union()` to combine the values of the sets `consonants` and `vowels`.

Use `print()` to output `alphabet`.