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Welcome back.

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So you've already learned
that functions and

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methods can return any kind of
value as their return value.

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But one thing that's worth noting is
that they can specifically return

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other instances.

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So let's suppose that we
have this Point class.

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And this Point class has a constructor,
and

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the constructor sets two
instance variables for x and y.

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And we have methods getX to
return the x instance variable,

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getY to return the y instance variable.

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And then distancefromOrigin to return
how far x and y are from the origin.

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Now, suppose that we wanted
to define a new method here.

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Suppose that we wanted the ability
to accept two points and

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return a new point that was
halfway between the two.

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So for example, here I have point p,
and I have point q.

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And let's say that we wanted a function
that would return a new point

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that was halfway between point p and
point q.

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And let's call that function halfway, and
let's make it a method on every point.

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So for example, if I say p.halfway when

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called with q, then this should return

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a new Point that is halfway between p and
q.

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So if I call this midway, so
I'll say mid = p.halfway(q),

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then I want this to return a new point.

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In this case, the x should be halfway
between 3 and 5, so the x should be 4.

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And the y should be halfway between 4 and
12, so the y should be 8.

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So let's define that method.

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So I'm going to say def halfway,
Like every method, it accepts self.

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And then I have a target.

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And we want to return a new point that's
halfway between self and target, so

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I'll say the x.

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So the mid x is equal to the average
between self.x and target.x.

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So self.x + target.x divided by 2.

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Mid y = self.y + target.y divided by 2.

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And I can return a new point, return
Point whose x is mx and whose y is my.

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And now if I print out what
the value of mid is, And

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run my code,
Then I'll see that I get x = 4,

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which is halfway between 3 and 5.

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And I'll see that y is 8,
which is halfway between 4 and 12.

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And again, note that mid is a new
instance of my Point class.

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So I can do things like
print out mid.getX,

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and I can print out mid.getY.

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And I'll get 4 and
8 respectively for those values.

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That's all for now, until next time.