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Okay, now that we've tackled sending a
single value to a function with arguments

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and parameters, let's talk about
sending multiple values to functions.

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The truth is,
there really isn't much of a difference.

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You can send as many arguments
to a function as you want, so

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long as it has a corresponding parameter.

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You simply separate the values with
a comma when you call the function, and

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separate the parameters with
a comma in the function definition.

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Let's revisit the add_two function and
expand on it.

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To recap, the add_two function
receives one argument.

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Stores the value of that
argument in the parameter num.

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Then adds two to that parameter.

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Then it returns the sum.

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What if instead we wanted a function that
would add any two integers together?

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To do this we could send two integers
to the function when we call it and

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rewrite or function a little so
that it can receive two arguments.

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Just follow along with me here and in a
little while you'll have an opportunity to

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open up your workspace and
try by yourself.

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First, we'll modify the function so
we can receive a second parameter.

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I'll change this first parameter to num1
and then add a second one called num2.

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As you can see, all I did to make this
happen was add a second parameter

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separated from the first by a comma.

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It's important to note that no two
parameters can have the same name.

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If you give two parameters the same
name the Python interpreter will send

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an error back.

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It's also very important to know that the
arguments will be received in the order

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that they are sent.

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The first argument in the function call
will always be received into the first

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parameter in the function definition.

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This is why these are called
positional arguments,

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the order in which you send them matters.

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The position of the argument must
correspond with the position

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of the parameter.

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Okay, now, in the body of the function
let's edit the expression that's assigned

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to the val variable, so
it adds these two new parameters together.

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Also, since the function was updated and
does something different now,

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I'll also change the function name
to something that's more accurate.

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And finally, let's fix our function call
to reflect the new function name and

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the additional parameter.

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And so, for the second argument I'll
just pick the integer 10 to send.

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Now, I'm gonna add a print statement
around our function call so

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we can see the outcome of our changes
when we save and run the program.

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All right, now, I'm gonna save and
run down in our terminal.

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Awesome, it printed out 15 which
is in fact the sum of 5 and 10.

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Now, it's your turn.

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Open up the attached workspace.

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Inside you'll see the unmodified add two
function and a call to that function.

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After pausing the video here try to
change up the add_two function so

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that it receives two arguments.

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The body of the function should multiply
these two arguments together and

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then it should return that value.

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After that edit the function
called to reflect the new number

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of required arguments and
the new function name.

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When you're done check the teacher's
note for the solution and

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then unpause the video.

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Welcome back,
I hope that was a fun challenge for you.

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How did it go?

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Before moving on the the next stage,

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why don't you take a few moments to
play around with your updated function.

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What happens if you don't
pass two arguments?

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What happens if you pass
a string instead of an integer?

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Try adding a third parameter and argument.

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Have fun with it and poke around
before joining me in the next and

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final stage of this course.

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Keep on coding.