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- [Instructor] Okay, the other stuff

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is pretty straightforward.

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Here's what the syntax looks like for boolean expressions.

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You can use a double equal sign to test for equality.

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And you can also just use the word is.

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There's also a triple equal sign that you can use

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to compare actual objects together instead of their values

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but that's seen less commonly.

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True and false are a little weird

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in that they are capitalized in Python

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but only the first letter like so.

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And for operators like and, or, and not,

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you just use the words and, or, and not

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instead of special symbols.

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You can do something like a case or switch statement

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by using boolean expressions

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with an if, elif, else structure like this.

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In this example, we print "How did that happen"

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if one is three which always false, otherwise we move on

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to test whether one is greater than three,

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which should also be met with disbelief if it were true,

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when that test fails we fall back

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to our final else clause

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which prints "All is well with the world."

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Again, we use indents to associate code

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with specific clauses here.

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We touched on looping earlier.

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Let's go into more depth here.

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You can use the range function

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to automatically build up a list of values

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within a giving range like so.

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Again, we start counting from zero here

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so range 10 gives us back the values zero through nine.

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The continue key word within a loop means

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to skip the rest of the iteration

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and go straight to the next one.

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And the break key word means to stop the iteration early.

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In this example, we use continue to skip over the printing

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of each value if the value is one, and we use break

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to stop after we reach the value five,

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Study the output of zero, two, three, four, five.

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And you'll see that's exactly what it did.

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An alternative syntax is the while loop

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which iterates until some boolean expression is false.

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Here we setup a counter variable called x,

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and loop through printing x only while x is less than 10.

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Once it hits 10, the loop ends as you can see in its output.

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So try out a really simple activity that pieces together

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some of the stuff we've just talked about.

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Your challenge is to write a block of code here

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that creates a list of integers,

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loops through each element of the list,

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and only prints out even numbers in the list.

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This should just be a matter of rearranging some

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of the other code in this notebook.

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So even if your not comfortable with Python,

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I encourage you to give it a try.

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You'll feel a lot better with Python

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if you've written something yourself with it,

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no matter how small.

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Okay, so hopefully you didn't have much trouble with that.

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Here's my solution, and keep in mind

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there's more than one way to do it.

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Let's type in myList equals, in square brackets,

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zero, one, two, five, eight, three.

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And you can use any numbers that you want.

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Then we can say for number in myList, colon,

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of course you might choose different variable names,

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if number

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mod two

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is zero, colon,

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print number.

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And as you can see, we do get the expected output

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of just the even numbers here.

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Okay, so that's everything that's peculiar about Python

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for the most part.

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If you're coming from some other language,

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that should give you enough knowledge

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to understand the Python code I'll be showing you

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in this course and to work with that code yourself.

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But if you're really befuddled at this point,

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I do encourage you to grab a larger

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introductory Python course before moving forward

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in this one.

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An ability to read Python code is going

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to help this course make a lot more sense to you.

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But if you think you got the basics here,

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let's move forward.