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Functions functions functions there are two types of functions.

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Bilstein and custom building functions are functions that have already been created by Python authors

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and are to use from Python programmers which is always a print function.

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It's an example of for beauty in function

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but in this lecture we're going to talk about Kasa functions and custom functions are super useful.

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I'll referred to custom functions as just functions from now on.

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So a function is an algorithm but even by us that computes in alterable given a certain input.

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The key benefit of function is that.

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Or you can write a function only once but you can use it as many times as you want by just calling it.

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Which is very simple.

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Here is how to write a function in Python.

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I'm going to create a function here that calculates the coast of potatoes unit price and the amount.

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So we use the word keyword def to tell Python that we are about to define a function and after that

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we choose a name for our function.

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I will name my faction but take two cost.

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Once we are either a function name we said the input parameters for the function and we can now write

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what function will compute and what it turns out.

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In this case we want to compute the cost of potatoes given the price on them and so close equals potato

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price dimes and moaned and we also want let's say to print out the potato type.

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Now we are printing all the potato type but we also want to return the calculated closed where the function

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is executed later.

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We can either do it using the print function or we can use the return keyword.

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I'm using the return keyword here and see now how easy it is to call the function once we have created

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it.

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So potato goes and we write the values which are called attributes.

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Now notice that we are imputing values for each of the parameters in the given order and what we get

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is a printed potato type and the computed cost.

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You can now execute the function as many times as you want using different values.

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And the last thing to mention here is that we are old fashioned in the Python console as I have told

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you before.

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This is a platform for testing.

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If we close I on we will lose our function the Phoenician will not be able to call it anymore.

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So normally we want to store our function in a script for later use.

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In that case we have to write it in a dot by script.

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Once we do that we can't really use the function in the future.

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So that was how to define and call a function.