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- [Instructor] Now that
you've seen how to implement

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a function that can receive
an arbitrary argument list,

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we'd like you to define your own function

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called Calculate Product that
receives an arbitrary number

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of arguments and returns the result

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of multiplying all of
those arguments together,

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the product of those arguments.

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So go ahead and implement that function,

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and try calling it with 10, 20 and 30.

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Then I want you to use
this Range calculation,

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which remember is going to
create a sequence of values,

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and I want you to unpack
that range of values

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as the argument to the
Calculate Product function,

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and call the function with that.

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So go ahead and pause the video to give

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those two exercises a shot,
and when you come back,

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you can see the answer.

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Okay, so first let's go ahead and define

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the Calculate Product function.

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So just like our Average
function, we are specifying

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just one parameter, in this case, which is

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the star args parameter,
indicating an arbitrary

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number of arguments, and
to calculate the product

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of all those values, what
we did here is we defined

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a local variable called
Product Initialized to One,

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then for every one of the
values in the tuple Args,

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we're going to iterate through
that and multiply product

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by the current value during
each iteration of the loop.

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When we finish that loop,
we'll have the total product

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in the variable called Product,

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and we can simply return that.

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Now there's also functional
style programming capabilities

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in Python that would
enable you to implement

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a reduction like this in
a single line of code,

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and we'll discuss items
like that in later lessons.

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So that's the definition of
our Calculate Product function.

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Let's take a look at the first
call to calculate product,

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so here we have the three
individual arguments,

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10, 20 and 30, these will
be packed into a tuple

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that will get assigned
to the Args parameter.

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Automatically, the
interpreter will handle that.

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And then of course, we
are iterating through each

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of those elements to access
and use their values.

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So 10 times 20 times 30
gives me the product 6,000.

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Now, you may be wondering
how to use the Range function

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as described by this exercise.

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You literally put the star in
front of the call to range.

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So this is going to produce
a sequence of values

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from one to six, incrementing
by two each time,

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so we'll have one, three and five.

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And we're going to unpack
those values and calculate

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the product of those
values, and you can see

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one times three times five
gives me the product 15.