WEBVTT
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Now that we've managed to create a question bank
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which consists of a list of question
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objects, the next natural thing to do is to actually bring up one of those
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questions and to ask the user to answer the question. Now,
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for all of the questioning and quizzing functionality,
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we're going to put that into the QuizBrain,
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which is going to be a class in its own right.
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And it's going to manage everything from asking the user for the next question,
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checking whether if the answer was right and also checking to see if we're
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actually at the end of the quiz.
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You're going to be creating this QuizBrain and class
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and this class is going to have two attributes to begin with; a question number
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which is going to have a default value of zero
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because all our quizzes will start from the first question.
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And this is going to keep track of which question the user is currently on.
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And we're going to use that number to go through the list of questions
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which will be passed over to this QuizBrain object when it gets initialized.
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And then you're going to have a method which is called next_question
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which will pull up the question from that list
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depending on which current question number we're on.
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If you take a look at the final version of the quiz game,
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you can see that it displays the question number, Q. and then that number.
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And then it displays the question text,
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and then it asks the user for an input, true or false.
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This is what we're going to be focusing on in this lesson.
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Inside your quiz-game-start,
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go to the quiz_brain file and create the quiz brain class.
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Add those two attributes; one is the question number
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which starts out with a default value and the other is the question list
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which is going to be initialized when you create a new quiz brain.
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And we're going to be passing over this question bank here into this question
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list when we initialize a new QuizBrain.
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Pause the video and see if you can complete this challenge.
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Right?
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All right. So let's start off by creating our new class
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which is going to be called QuizBrain and inside this class, we'll need to
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initialize some of those attributes,
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so I'm going to create the init method. Inside the init method
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I'm going to create that first attribute which was called question_number
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and I said we would set it to have a default value of zero.
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So this means every time we create a new QuizBrain
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object from this class,
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it's ready going to have an attribute called question_number that set to zero.
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Now the next attribute is called question_list,
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and this is not going to have a default value. Instead,
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it's going to get it as a value passed over.
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So lets put that as a q_list here and set it equal to question_list.
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So what's going to happen is inside our main.py file,
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we're going to be initializing that QuizBrain and the value that we're going to
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put in there as the question list is going to be the question bank. This way
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we'll receive the question bank and it will be inside this question list
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attribute. Now I have another challenge for you.
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Create a method called next_question inside the QuizBrain.
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This method needs to retrieve the item at the current question number from the
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question list. And once you have this item,
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use the input function to show the user the question text and ask for the
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user's answer. Pause the video and give this a go.
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Alright, here's the solution.
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First we're gonna define a new method called the next_question,
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and this method is basically going to get hold of the current question and that
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is of course going to be from the question list.
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And then we're going to tap into that list and get hold of the item at the
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current question_number. So for example,
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question_number is going to start out being zero
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and so it's going to go into this list
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which is basically going to be our list of questions from our main.py,
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so our question bank.
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And remember, each of the items inside that list is a question object and
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question objects have text attributes and answer attributes.
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So in addition to getting hold of the current question,
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we can then get hold of the current question text by taking the current question
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and then just simply writing .text to get the value that's saved in that
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attribute.
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We're going to use an input to ask the user for
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what their answer is to this question.
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This is going to be an fstring because we're going to be inserting the current_
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question.text. And at the very beginning
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if you remember,
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we also have the Q. and then the number and then the colon.
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So that will be the self.question_number.
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And then we've got our colon and then it's going to be the question text.
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And then we're going to ask the user for a input; true or false.
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And that's it. That completes the challenge.
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Now all that's left is to show the very first question to the user and run our
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code. Let's go back to the main.py and import the QuizBrain class.
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So we're going to say from the quiz_brain file import the QuizBrain class.
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And once we've created our question bank,
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then the next thing to do is to create our new quiz.
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So this is going to be a new QuizBrain object
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and when we initialize it, we have to pass in a list of questions.
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And that is of course going to be the question bank.
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So now that we've got our quiz up and running,
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then we can say quiz.next_question.
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Let's go ahead and run this main.py file.
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And you can see we get our question text being displayed, true or false being
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asked, but our question number starts from zero.
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And that is, of course,
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because we need zero here in order to get hold of the first question from the
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list and that's why this has a default value of zero.
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But by the time we reach this input,
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it would be really good if this actually read one instead of zero.
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So one way we could do this is we could do this plus one,
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but remembering that we actually need to increase the question number every
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single time we call next_question anyways,
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then once we've gotten hold of the current question,
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we can actually tap into that self.question_number and increase it by one.
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This will have the same effect,
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and if you look at it now we've got the right question number being shown here,
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the right text being shown, and then we can insert true or false.
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Now at this stage,
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our program is just going to exit. In the next lesson,
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we're going to have to work out a way for our questions to keep being asked. And
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we'll need to write some more code for that to work.