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You have completed Functions, Packing, and Unpacking!
You have completed Functions, Packing, and Unpacking!
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Create a function of your own.
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Now that we know a little bit
about what a function is,
0:00
let's look at how to write one.
0:02
Feel free to follow along from
the attached workspace, but
0:04
don't get too hung up on typing or
trying to copy me as I go.
0:07
There will be opportunities for
you to pause the video and
0:10
try things out on your own.
0:13
Functions serve the same purpose
in every programming language.
0:14
But the syntax for
0:17
writing them is going to be a little
different from one language to the next.
0:18
In Python you know you've encountered
a function when you see the keyword def
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that's D-E-F.
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Followed by a snake cased string,
0:27
which is the name of the function followed
by a set of parentheses and a colon.
0:29
Snake casing is when you string together
words using underscores instead of spaces.
0:33
Snake casing doesn't use
any capital letters.
0:38
For example, my name written in
snake case would be ashley_boucher.
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If you want to name your function with
multiple words, use snake casing.
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This is the Python style standard.
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Now I'm gonna write a simple function
called print name to show you the correct
0:53
format for a function definition.
0:57
So start with the keyword, def,
followed by the name of the function,
1:01
which is print_name in snake case,
then some parens and a colon.
1:05
That colon at the end indicates
the function is beginning.
1:09
What follows that colon will be the code
block that gets executed once the function
1:13
is called.
1:16
The contents of the function
must be indented four spaces.
1:18
In this case, the contents of the function
is just one line that prints a string.
1:21
That's it.
1:29
Now it's your turn.
1:31
Pause the video here and
in the attached workspace go ahead and
1:32
try to write your own function.
1:35
Name your function print favorite movie,
and
1:37
in the body of your function print
out the title of your favorite movie.
1:39
When you think you've got it,
unpause the video to go over the solution.
1:43
All right, how did it go?
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Were you able to write your function?
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Let's take a look.
1:51
The first thing you should
have is the keyword def.
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The def keyword should be followed
by the name of the function.
1:57
Did you remember to use snake
case to write the name?
2:00
It'll look like this.
2:02
Then one of parens, followed by a colon.
2:05
Finally, to write the body of
the function we add a new line,
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indent four spaces, and
print out the title of our favorite movie.
2:12
Don't forget to add quotes around
the movie title to indicate that
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it's a string.
2:23
Awesome work, now you know the basic
structure for writing a function.
2:25
You have a new tool in your tool belt that
is super critical to writing Python and
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computer programming in general.
2:32
The next step is learning
to use your function.
2:35
In other words, calling it so that
the code inside actually gets executed.
2:37
Join me in the next video to learn how.
2:42
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