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All right, let's go ahead and run through the solution together. Firstly,

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I'm going to fork my own copy of the starting file for step two

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and then I'm going to take a look at to-do number one.

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So the goal is to create an empty list called display,

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and for each letter in the chosen word,

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remember that a random word from this list,

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we're going to add an underscore to this list called display.

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So it tells us that if the word was apple,

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then display should contain five underscores representing each letter the

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user needs to guess.

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Let's go ahead and just click run before doing anything first.

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And this print statement will execute and it'll tell us that the solution is

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ardvark. This is a seven letter word. So in this case,

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we would need to create a list with seven underscores and seven items.

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Let's go ahead and create an empty list called display.

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An empty list is just a set of square brackets with nothing inside.

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Now, for each letter in the chosen word,

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we're going to add a underscore to this list.

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How can we add something for each letter?

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The simplest way is to simply use a for-loop. Now, in this case,

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we have a choice.

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We can either use the style of for-loop that we used previously down here,

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which is a way of looping through a list.

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So we could say for letter in chosen_word,

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so it's going to run this for as many letters as there are in this word.

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And for every single letter,

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we're just simply going to take our list, display, and add a item to it.

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And that item is going to be the string, underscore.

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So now if we go ahead and print out our display and see what we get.

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The solution is baboon

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which has six letters and display gets printed with one, two, three, four,

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five, six underscores inside.

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Now notice how here we're not actually using this variable letter that gets

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created. We're looping through every letter in the chosen word,

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but we're not doing anything with each of the letters. So we can in fact

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just replace it with an underscore. Now, alternatively,

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we could have created this for loop with a range function as well.

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And remember that the range function creates a range of numbers from zero up to

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a particular number that you specify. So we could have also,

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instead of looping through the chosen word, use range and inside here,

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we could have put the length of the chosen word.

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So then our range would be between zero and the length of the chosen word.

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So it was a baboon then it would be from zero to six, but not including six.

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Remember that's how the range operator works.

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So it would be zero and then it would be one and so on and so forth until it

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gets to five.

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And so that would be a total of six loops adding six of these underscores.

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So given that I've updated this for loop, if we run it again,

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you can see its exactly the same,

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it will create as many underscores in the list as there are letters in the

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chosen word. So it doesn't actually matter in this case

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which version you went for, either this version of the

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for loop using the range function or the previous one

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which just looped through the list. It's your choice. They both worked the same.

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So now let's move on to to-do number two.

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Now we have to loop through each position in the chosen word

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and if the letter at that position matches the letter the user guessed,

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then we're going to reveal that letter in the display at that position.

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So basically we're going to replace the underscore with the letter that the user

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guessed if they guessed it right.

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So now this is probably the hardest part of this whole step because in order to

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do this,

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we actually have to change this for loop to

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one that uses the range function because we need to get hold of the position

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when the letter and the guess actually matched. That way

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we can tap into the list and change only the item at that particular position.

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So let me show you how the code would look.

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Instead of saying for letter in chosen_word,

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we would say for position in range

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and the range is going to be between zero and the length of the chosen_word.

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And once we've got that, then the

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for-loop is going to run for as many times as there are letters in the word and

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for each of those letters

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it's going to give us a number, a position to work with.

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So the first time it runs it position is going to be equal to zero because we'll

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be looking at the first item in the chosen_word,

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which in this case would be a.

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And then the next time the loop runs position becomes one

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and we'll be looking at the second item in the list.

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Now we no longer have that letter to work with,

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which is why we get an error here.

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So how can we get hold of the current letter in the chosen word

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given that we know the position? Well,

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it would be as simple as saying letter = chosen_word 

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[position].

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Now we can check to see if the letter is equal to the letter

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the user guessed.

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Then we can get hold of our display and get the item at the current position and

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then set that to equal the letter.

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And we can get rid of the else statement entirely.

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So now notice that we're using the length of the chosen word in quite a few

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places. So if you want to,

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you can actually simplify the code by simply creating a new variable called word

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length.

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And now every time we need to use the word_length,

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we can just refer to that variable

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Right?

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which should make our code a little bit easier to read.

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Right?

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Finally, all we have to do for step three is just to print our list

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which is called display. And then when we run our code,

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you should be able to see that if the solution was camel,

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initially, our display starts out with five blanks because there's five letters.

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And then once we've guessed a letter,

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then it will replace that letter at the correct position in that display list.

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So a only matches the second letter,

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so that second blank gets replaced by this letter.

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And again,

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I recommend to review the code if it's at all confusing or if you didn't manage

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to get it first time through the Thonny IDE just to see it step by step and see

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what's actually happening. We've chosen our random word,

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which in this case turns out to be camel.

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And once we get into our display,

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it starts out as an empty list.

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But as soon as we calculate the word length,

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then we can go ahead and loop through the range of numbers from zero to the

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length of the word, which is five. And it will run the code in the

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for loop

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which is just to add the underscore to this list five times.

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And finally, once it's done, it's going to print it out.

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So this is what we get, five blanks for the word camel.

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Now it asked the user for a guess.

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So I'm going to guess that letter a and enters this final for loop.

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This is where it's really interesting.

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So we're going to step into it to see it in more detail.

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So now the range is a range between zero and the word length.

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So the word length is five

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so that range becomes from zero to five not

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including five. So zero, one, two, three, four.

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And that is going to make the for loop run five times.

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The position starts out with zero. And when position is zero

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then it's going to go into this next line, line 18, and put zero here as the

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position. And then we go into the chosen word,

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which is camel and pick out the item at position zero.

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And so this letter becomes equal to the letter c because that's the letter at

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position zero of the word. So now in our if statement,

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we check to see if the letter, which is c, is equal to the guess,

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which is a. Well in this case, c does not equal a

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so we go back to the beginning of the for loop and we go to the next number in

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the range, which is now one.

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And we're going to repeat this again and again. But in this case,

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notice that the letter at position one of camel is equal to a.

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So now letter is equal to a and guess is equal to a.

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So if those two are equal, then this

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if statement is true and we end up going inside it to carry out this

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functionality. Our letter is equal to a,

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and we're going to look at our list, which is called display, this one,

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and we're going to replace that second character with the letter that was

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matching. And it's going to do this again and again

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until we've looped through five times through all of the letters in the chosen

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word

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and finally we print the final version of display with the correct letters

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replaced. Have a play around with this

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if you're at all confused and it might be that you need to look up some stuff on

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Stack Overflow,

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or you might need to review some of the lessons that we've done before on things

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like range functions and for loops, just so that you're really,

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really certain that you know

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what's going on and only then should you continue to the next step.

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Take a moment with this and I'll see you on the next lesson.