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All right. So now we're on to the next dictionary comprehension exercise,

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which is day 26.5 dictionary comprehension two.

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And in this challenge,

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you are going to be converting a dictionary of temperatures in Celsius to their

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corresponding temperature in Fahrenheit.

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So this is how you convert a Celsius temperature to Fahrenheit.

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So the temperature multiplied by nine divided by five and then plus 32.

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So you saw this in a previous lesson as well. So pause the video,

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have a read of the instructions, take a look at the hints

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if you get stuck and see if you can complete this challenge.

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So in this case, 

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we have a slightly different exercise from before because we're now going to be

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working with a dictionary to create a new dictionary.

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Let's write our code here and let's create our new variable

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which needs to be called weather_f. And this

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weather_f is going to be a new dictionary.

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Let's put in our keyword method to

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create a new dictionary from a dictionary.

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So new_key:new_value for,

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and then it's parentheses key,

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value. So, be really careful here.

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I've seen a lot of students just use the colon in this case,

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but it's actually a tuple. So it should be key, value.

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And then we specify the dictionary that we want to loop through.

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And then we call .items on it. And remember, this is a method,

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so it needs the parentheses at the end.

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So now let's replace the relevant parts of this line.

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So our dictionary is going to be this one,

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our weather_c. That's the dictionary we're looping through.

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And we're gonna get a hold of all of the items in that dictionary

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and then get each of the keys which I'll call day, and value

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which I'll call temp_c because it will be the temperature in Celsius.

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So now that I'm looping through each of the days and the temperatures in our

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weather dictionary, then we're going to create our new key and new value.

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So the new key is actually still going to be the same day.

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It's going to be unchanged because we want this as our output

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and it looks pretty much the same as this one,

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other than the fact that we've converted the value.

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So the new value though is going to be calculated using this formula.

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So we're going to take our temp_c and then we're going to multiply it by nine

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divided by five. And then we're going to add 32. If you want,

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you can add the parentheses around this line,

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but because we're doing math and we're going from left to right,

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and we're first doing multiply divide, then we do add and subtract,

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then it's actually completely optional in this case.

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But we'll just include it in there for completion sake. So now when I hit run,

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you'll see that

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I've got a dictionary that's being generated with each of the days in the week

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from this dictionary

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and each of the temperatures have been converted to Fahrenheit.

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So this is super useful

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and you often find yourself needing to work with values in a dictionary.