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Now the reason why we're learning about list comprehensions is because when we

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created all US states game,

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I realized that the code that we were writing could be a lot shorter if only we

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knew about list comprehensions.

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So I want you to head back over to your code for the US states game and open it

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up. And I want you to look at this if statement.

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So when the user types exit,

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we create a new list of missing states in order to save it to a CSV file.

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I want you to change this code

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using your new knowledge of this comprehension and see if you can cut down this

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code by three or four lines.

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Pause the video and complete this challenge now.

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All right. So instead of all of this, creating a new empty missing state

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and then going through a for loop, we can simply do this in one line. So again,

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it's going to be called missing_states and this is going to be a new list,

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but this time it's going to be created using our list comprehension;

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new item for item in list

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if test.

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The list in this case that we're looping through is all of our states.

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So we're gonna replace that with all states. Now,

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each of the items is basically a state in that list.

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And the test that we're going to make is to see well if the state is not in the

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guessed_states which has states added every time

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the user makes a correct guess

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so we can basically take this part of our previous code and put it here.

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And in that case, then we're going to add this particular state

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which pass this test into this new list.

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This one line

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basically will replace all four of these lines and it cuts down dramatically

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on the amount of code.

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And it reads relatively well as well. Add a state to this new list

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if we loop through all the states in the list of states

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and if that state is not in this list of guessed

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states. List

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comprehensions are super popular with Python developers and I hope through some

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of these exercises

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you can see why, just in terms of the sheer amount of code that it cuts down on

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and how much it simplifies things. Now,

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in addition to list comprehensions,

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we can also do comprehensions with dictionaries. So in the next lesson,

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that's what we're going to be looking at.