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Let's talk about 'args' and 'kwargs'.

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'args' are arguments, and 'kwargs' are key word arguments.

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Keyword is one word I think, keyword arguments.

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So what you're going to see in the while, in other people's

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code is something like, 'def', you've got a 'func_name' in here,

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some function name,

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it's going to take some sort of parameter,

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let's say it takes a 'name', and then has '*args' and then '**kwargs'.

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Now, '*args' can technically be named anything, but it is denoted

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by a single asterisk.

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This means that there are going to be other arguments in

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this function. And keyword arguments,

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again, this could be called anything else, but by convention,

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we call this 'kwargs',

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and this one is 'args'.

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This one is denoted with two asterisks, '**' before it.

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So let's go ahead and explore some 'args' first.

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So let's go ahead and just say '*args',

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and in our function, we're simply going to loop through these 'args'.

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But first, I want to actually print out what 'args' is.

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'print(args)', and notice that there is asterisk in here.

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This is simply saying that, "Hey, there's going to be other

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arguments in here, and use 'args' as the variable name in here.

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So 'print(args)'.

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Let's also 'print(type(args))'.

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What is this going to be?

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And let's run 'def func_name' here.

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'(1, 5, 8, 'Python', Coding')'. I don't know.

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I'm just filling with some random stuff in here.

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And we can see when we print the arguments

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this is a tuple.

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And so the 'args' are a tuple, means they cannot be changed.

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We can't add more values to the arguments.

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We simply cannot do that because tuples don't allow us to do that.

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They're immutable. Which means we're stuck with the

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values that come in here.

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Doesn't mean we have to use them,

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but we cannot change 'args' as a variable name inside of this

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function. Once it is set, it is set in stone.

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So let's see how we can access these arguments here.

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'def', we're going to call this one 'print_args', and it's going

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to take any number of arguments,

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and it could be literally any number of arguments.

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It could be 1, it could be 0,

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it could be a 1000. 'for arg in args', we could simply print

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the argument value, whatever that is going to be.

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And so if we say 'print_args('Computer', 'Coffee', 'Cup', 'Monitor',

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'Lamp')', these are literally just things that I can see

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on my desk right now.

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This function is going to go through all of these arguments,

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and just going to print them out for us.

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Go through each 'arg' one by 1.

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Now that is a standard argument,

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but we also have these things called 'kwargs',

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keyword arguments.

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Keyword arguments are like what we saw in the last video

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where the 'role' was 'Student' by default.

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Let's go ahead and create an example here.

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'def my_func', and it's going to take not 'args', but just 'kwargs',

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so '**kwargs', and let's print out what 'kwargs' is going to be,

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and let's also print out the 'type(kwargs)',

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so we know what we're working with.

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[no audio]

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and 'my_func', and

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this is going to take keyword argument,

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that's what 'kwargs' is,

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keyword arguments. 'name = 'Kalob', 'drink' = 'Coffee', is equal

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'hobby =', not 'Planting', 'Gardening', something like

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that, and that is not going to work because I typoed the

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function name. There we go.

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So this came back as a dictionary. 'print(type(

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kwargs))', came back as a dictionary, and we get a key:value,

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key:value, key:value. So that's interesting.

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Now we have something to work with.

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We know about tuples, we know about dictionaries,

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we have something to work with here.

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So let's go ahead and take this exact same example,

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but let's loop through every key:value, and just print it back.

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So we could say, 'for key, value in kwargs.items'.

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We know it's a dictionary, and we can use '.items' on it.

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'print("Key:', is going to be whatever the 'key' is going to be,

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let's go ahead put an arrow in here or not an arrow,

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let's do a few tabs, and then the "Value:" is going to be whatever

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the 'value' is going to be.

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And let's take this exact example again, and we can see 'key'

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is equal to 'name', the 'value' is 'Kalob'; 'drink', 'Coffee'; 'hobby', 'Gardening'.

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Now, at this point in time, this is actually super useless

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because you're never really going to do this in real Python

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programming. But let's say you're going to order food from

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a food ordering company. I don't know,

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"Uber Eats", "SkipTheDishes", "DoorDash", whatever company,

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they're going to have some sort of function or a series of

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functions that's going to accept an order.

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So let's create an 'order()' function in here, and it needs to

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take your 'name' because they need to know who to deliver to.

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We could also say, it needs to take your address, but that's

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getting a little too complicated, a little too much information,

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you'll just watch me type for too long.

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So it's going to take someone's 'name', and maybe some other notes,

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some other keyword 'args', or just 'args', not keyword 'args',

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and then it's also going to take some 'kwargs'.

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And this is going to say 'print("Hello", )'.

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This is an f-string.

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So let's go ahead and throw an 'f"' at the beginning of that.

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The other 'args' in here could be different dishes that you want.

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So we could say 'for arg in args: print(

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"\t You ordered, You ordered an ", and that's an f-string as well.

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Now, to make this a little simpler, we could actually change this

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from 'args' to 'dishes',

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[no audio]

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and let's call this 'dish' and "You ordered a ".

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And we could also check to see if someone's address,

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this is a good example, if someone's address is in the keyword

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'args', so we can say 'if kwargs.get("address")

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print("\t

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We are delivering to )'.

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And let's reassign this.

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That's also an f-string,

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so boop little 'f"' there.

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And let's create 'address = kwargs.get('address')'.

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And this is only going to show up if address is actually

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in one of the keyword 'args'.

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So let's hit 'Enter' there, and let's create an 'order'.

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An 'order' is going to be 'for', "Zephyr",

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he's going to order "tacos" and also "cat food", because he's

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a cat, and his address is a keyword argument.

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His address is going to be, "123 Meow Lane"

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And look at that it says, "Hello Zephyr

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"You ordered tacos". "You ordered an tacos".

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"You ordered tacos". "You ordered cat food". And, "We are going to

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deliver to 123 Meow Lane".

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Let's go ahead and rerun this without an 'address'.

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Let's see what happens.

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And let's also get rid of 'an', because that's just bad grammar.

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There were no keyword arguments provided.

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And 'address', where we saw 'address =', does not exist.

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So it's skipped over this because it didn't exist.

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So the 'it' statement was never triggered.

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In fact, we can actually do something a little more explicit

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here and say, 'print("You', all caps, let's yell at the person

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"YOU DID NOT PROVIDE AN ADDRESS WOW

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CMON")'. Let's rerun that one.

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Let's rerun that one.

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It says, "YOU DID NOT PROVIDE AN ADDRESS WOW"

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'address',

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and this could be anything at this point, anything.

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[no audio]

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So this is a little bit of an example, a fairly good example

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that I think a lot of people can relate to these days,

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where your ordering food,

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you need a name because your account has a name,

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they need to know what dishes you're ordering, which could

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be any number of arguments and also keyword arguments,

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things like your address or any special delivery note could

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be a keyword argument.

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So why is this important?

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Because in the wild, especially in web frameworks like Django

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or Flask, you're going to see a lot of function parameters

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where you just have a regular argument,

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and then you've got unlimited arguments, and then you have

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keyword args, and you're going to see these working together

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all the time.