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Now that we know different
ways to make sets,

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let's learn about how to manipulate them.

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We'll start with adding and
removing elements.

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Remember that sets are mutable,
that means,

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that the data inside of a set can be
changed after the set is created.

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There are two methods for
adding elements to a set.

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If an element is already a member,
there is no effect.

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We can add one element at
a time with the add method, and

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we can add many elements all at
once with the update method.

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Let's demonstrate! First,
I'll declare a new variable,

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let's have vowels and
assign it as an empty set.

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Then, we can use the add
method to add one element,

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And I'll add in, A, which was
the first vowel, we'll do a capital A.

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So if I print my vowels out, and

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I run my script in the console

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I'll see that I have a set.

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It's a singleton set with one member and
the member is a capital A.

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This method has no effect if an element
is already a member of the set.

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We'll make a simple check for
membership using the "in" keyword.

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And what I'll do here is I will print out...

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We see it's true that A is
a member of this set of vowels.

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Now what will happen if I duplicate and

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add in this A many, many times.

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When I run my script again,
we'll see that I still have a singleton

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set! Because A is already a member of
vowels, it will not be added again.

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Now, instead of adding in the rest
of the vowels one by one,

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let's add them all together.

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I can use the update method
to add multiple values.

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It takes an iterable as an argument,
just like the set constructor function.

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I'll use my favorite iterable
type, which is a string

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E, I, O, and
U. Just like the set constructor function,

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the update function will go through
every element of the iterable,

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and then add it into the set.

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Let's print out my new vowel
set after it has been updated.

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We'll see all of the vowels
have been added into the set.

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When elements are already a member of
the set, the method will have no effect.

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We can see that even though I've
tried to add the letter A many times,

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and then the letters E,
I, O and U many times,

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they're only added into the set just once.

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So, there's our set of vowels.

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Notice how the order is non-deterministic
for these string data types.

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So if your vowels come
out in a different order,

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that's totally okay,
it's working as intended.

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Add and update are the two methods for
adding elements into a set.

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Next we'll learn about
removing elements from a set.