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Instructor: Let's go back to our example of our game

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where we have a user login

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and they have to provide their age.

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Remember, if I click "run,"

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it's going to ask me, "Hey, what's your age?"

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And if I give it something that it doesn't like,

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it's going to keep asking me

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until I provide a proper value.

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There's one other piece to the try/except lock

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that we haven't covered.

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So we know that we have "try,"

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we have "except,"

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and then we have "else."

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But there's also another thing called "finally,"

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and finally runs at the end

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after everything has been executed.

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Let me show you.

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If I do print, let's say, "Okay, I'm finally done."

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Let's see what happens.

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If I click run here and I give it a proper age

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I get "thank you" because my try block succeeded.

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Nothing has failed.

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I go to the else and I say "thank you."

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And now I break out of the while loop,

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but finally says,

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"Hey, no matter what,

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at the end of it all, I want you to finally do something."

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Let's see this in action

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if I do something like zero.

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I get, "Please enter age higher than zero."

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But then also still get, "Okay, I'm finally done."

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What if I enter gibberish?

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I get, "Hey, please enter a number,"

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but also, "Okay, I'm finally done."

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So finally runs regardless at the end of everything.

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Why is this useful?

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Maybe you're working on a game server

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and you wanna make sure that you log out

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any activity on the server.

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So, let's say a user tries to log in.

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Even if they try to enter the wrong information,

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we want to log that activity,

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so that maybe we can detect

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that there's people trying to break our program,

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or just to have our records that,

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"Hey, this user has tried to log in 10 times."

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So finally is very useful.

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Now let me ask you a question.

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What happens if I do something like this?

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Let's say I have here "continue,"

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and maybe another break statement here,

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and then maybe inside of here,

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I'm also going to have a print,

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"Can you hear me?"

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What happens if I do something like this?

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Pause the video if you need to.

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Otherwise, I'm going to hit "run,"

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and see what's going to happen.

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What is going to happen if I enter zero?

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Ready?

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I get, "Please enter age higher than zero,"

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because I get a ZeroDivisionError.

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It catches here, and then we break out of the loop.

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The finally gets run, but print never runs because,

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well, we break out of the loop.

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And remember, this is surrounded by the loop.

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Let me remove this so we can see it better.

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Okay, what happens if I do something like this?

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What if we run the program again

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and this time give it gibberish?

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Let's find out.

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I get, "Please enter a number. Okay, I'm finally done,"

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and then, "What's your age?"

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So what happened here?

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Well, we tried this,

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we got an error, a value error.

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It says, "Hey, please enter a number,"

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and then it's going to continue.

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Now continue instead of break

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doesn't break out of the loop, out of the while loop.

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Instead it comes back to the top.

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So it's going to try again.

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This part, "What's your age?"

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Okay, so what if we finally try to log in properly

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and give it, "Hey, we're 18."

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What happens then?

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There you go.

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I get, "Thank you,"

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because we've tried it, everything works.

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So, no exception.

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So we are gonna get "thank you"

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and then we break out of the loop.

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So once again, this print never gets printed,

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"Can you hear me?"

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But then finally, "Okay, finally is done."

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If we didn't have this break statement here

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and I click "run,"

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and give it "18," oh boy,

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"Finally I can hear you."

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This print finally gets printed

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because we don't break out of here.

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We don't break out of here, and then we run this line.

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Hopefully that makes sense.

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That was a bit of a trick question

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but you're starting to get the hang of it.

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I'll see you in the next video.

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Bye, bye.