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Once you've unzipped and opened up the starting file inside PyCharm,

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this is what you'd see.

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There is a CSV file that contains each of the letters and the code word,

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and there's also our main.py with some of the example code that I showed you

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in the last lesson. Now,

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if you don't know how to complete this challenge, especially step 1,

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I really urge you to go through this example code and just go through each of

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the different types of loops and see what it is that you get when you print the

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key or the value. And in this case, when you print the index

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or when you print the row. And then see what happens when you get hold of some of

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the items in the row. And seeing how maybe the row.student or the row.

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score works. Once you fully understood this,

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then it should be relatively easy to complete step 1.

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So essentially the goal is that we want to create a dictionary that looks like

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this from the CSV.

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The first thing we have to do is to go ahead and import pandas.

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And if you need to install it, there should be a squiggly line

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and then you can click on it

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and the light bulb will help you install the pandas module.

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But once we've gotten hold of the pandas,

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we can go ahead and use it to read CSV from our file

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which is this file. It's under the file path of just nato_phonetic_

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alphabet.csv. So it will save this as our data

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which is basically going to be our data frame. Now,

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once we've got hold of our data,

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then you can see that if we print this out,

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it looks like this.

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But if we use that method, to_dict, and then we try to print it out,

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you can see that it's not organized the dictionary in the format that we want it

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to, which is to have the letter as the key,

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the corresponding code as the value. In order to complete step 1

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as I mentioned, we're going to have to use dictionary comprehension.

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And the method is going to be using the iterrows to iterate through each of the

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rows inside that data frame. So I'm going to copy that line here,

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and I'm going to paste it in here.

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Now, this is the format, so let's go ahead and replace each of the keywords.

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Our data frame, in our case, is just called data.

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And then we're going to say data iterate through each of the rows,

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and then for each of the index and the row,

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we're going to do something with it.

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Now the new key is going to be the row.letter and the new value is going to

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come from that row as well and it's going to be row.code.

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So this is the code that will create our new dictionary

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and I'm going to call this our phonetic_dictionary.

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Now, if I print that out,

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you can see that this is the straight up data.to_dict

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and then the second line is the one where we've actually formatted it

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using what we've learned about dictionary comprehension.

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Once we've gotten hold of this phonetic dictionary,

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then to do step 2 is incredibly easy because all we have to do is to create

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some sort of inputs, ask the user to enter a word,

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and then we can save this input to a variable. Now,

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once they've entered the word,

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we have to check it against each of the keys inside this phonetic dictionary.

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So notice how each of the keys all uppercased.

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So we're going to have to change whatever it is that the user has inputted all

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to upper. So that way, if they entered a lowercase or an uppercase,

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it doesn't really matter because we're going to convert the whole string to

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uppercase. And then we're going to use our list comprehension.

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The way we create our list comprehension is going to be new item for item in

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list. So in this case,

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our list or the thing that we're going to iterate through is going to be our

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word.

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And then we're going to go through each of the letters in the word.

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And once we have each of the letters,

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we're going to go through our phonetic dictionary, this one right here,

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and pick out the value that corresponds to the particular letter that we're

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iterating on.

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So we're going to use the square brackets and then pass in the letter like this.

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Now we've created our output list and we can go ahead and print it out.

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Now let's go ahead and comment out this line and run our code.

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So it's going to ask me to enter a word, I'm going to enter my name.

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And now it's managed to convert that into a list of phonetic alphabets that

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corresponds to each of the letters in that word.

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Did you manage to complete this challenge? And if not,

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which part did you stumble on?

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Was it the part where you were using the iterrows? If so,

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then go back to the starting file for this project and go through each of the

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different ways that we're looping through it and use print statements to really

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understand how the loop is actually going through and looking through the data.

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Now,

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if on the other hand, it was the dictionary comprehension or the list

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comprehension,

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then be sure to go back to the relevant lesson and just make sure that you

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review it and you write out the code in the lesson for yourself

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just to be sure that you understand what's going on before you continue to the

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next day.