1 00:00:00,300 --> 00:00:00,630 All right. 2 00:00:00,630 --> 00:00:04,620 It's time to put what you've learned to practice and see if you can complete 3 00:00:04,620 --> 00:00:07,110 these challenges on dictionary comprehension. 4 00:00:07,710 --> 00:00:12,690 So I want you to find the exercise that is day 26.4. 5 00:00:13,350 --> 00:00:17,190 Now, once you've found day 26.4 dictionary comprehension one, 6 00:00:17,460 --> 00:00:21,030 you'll see that this is the starting code I have for you. 7 00:00:21,030 --> 00:00:22,530 I've got a sentence here 8 00:00:22,710 --> 00:00:26,640 which is a string and your job is to count 9 00:00:26,730 --> 00:00:31,350 how many letters there are in each word and create a dictionary that looks like 10 00:00:31,350 --> 00:00:32,183 this. 11 00:00:32,220 --> 00:00:36,060 So your final dictionary is going to be saved as this variable called 12 00:00:36,060 --> 00:00:38,700 result and it's going to be printed to the console. 13 00:00:39,420 --> 00:00:41,130 Have a read of the instructions, 14 00:00:41,490 --> 00:00:45,270 especially be aware that you might need to do some Googling to figure out how to 15 00:00:45,270 --> 00:00:49,620 convert a sentence into a list of words and use the hints if you need them. 16 00:00:50,070 --> 00:00:52,230 So pause the video and give that a go now. 17 00:00:53,300 --> 00:00:54,133 Okay. 18 00:00:57,170 --> 00:01:01,010 The biggest hurdle of this challenge is not actually the dictionary 19 00:01:01,010 --> 00:01:01,843 comprehension. 20 00:01:02,210 --> 00:01:07,210 It's the figuring of out how to convert a sentence, a string, into a list of words. 21 00:01:08,360 --> 00:01:13,190 So I've basically just typed out the entire query with Python at the end into 22 00:01:13,190 --> 00:01:17,060 Google. And if I click on the first Stack Overflow answer, 23 00:01:17,330 --> 00:01:22,250 you can see that they're telling you that you should probably investigate the split 24 00:01:22,310 --> 00:01:23,143 method. 25 00:01:23,450 --> 00:01:28,450 The split method basically splits a string by space and converts it into a list. 26 00:01:28,910 --> 00:01:32,450 That's exactly what we need in order to solve this challenge. 27 00:01:32,930 --> 00:01:37,930 And also in the hints, you can see that I've linked it to a page in the W3 28 00:01:38,240 --> 00:01:40,400 Schools documentation for Python. 29 00:01:40,850 --> 00:01:43,970 And I like looking to the W3Schools just because you have the 30 00:01:43,970 --> 00:01:45,080 try-it-yourself section 31 00:01:45,080 --> 00:01:50,080 where you can actually run the code and see what is the result of running this 32 00:01:50,570 --> 00:01:53,600 method. So if you have a sentence, Welcome to the jungle, 33 00:01:53,630 --> 00:01:55,250 once you call split on it, 34 00:01:55,490 --> 00:01:59,780 it creates a list with each word as a separate item in the list. 35 00:02:00,530 --> 00:02:03,680 Now we're basically ready to tackle our challenge. 36 00:02:04,520 --> 00:02:09,140 We're going to create our result which is going to be a dictionary. 37 00:02:09,620 --> 00:02:14,420 So let's start out with the keyword methods. So we'll say new_key: 38 00:02:14,450 --> 00:02:19,450 new_value for item in list. 39 00:02:20,570 --> 00:02:21,470 Now, in this case, 40 00:02:21,500 --> 00:02:26,500 we're not actually iterating through a dictionary and we're only iterating 41 00:02:27,140 --> 00:02:29,780 through a string, which is just a sequence. 42 00:02:30,200 --> 00:02:35,150 So we can replace this list with our sentence, but we can't leave it at 43 00:02:35,180 --> 00:02:40,010 just the sentence, because then it's going to loop through each of the letters. 44 00:02:40,520 --> 00:02:44,120 So instead of having it as just the sentence string, 45 00:02:44,210 --> 00:02:49,210 we're going to use the split method to convert it into a list of words. 46 00:02:50,390 --> 00:02:53,540 And once we've done that, then every time we loop through it, 47 00:02:53,600 --> 00:02:58,040 we're actually looping through each word in this list. 48 00:02:58,930 --> 00:03:01,840 And it's usually a good idea to test out the code. 49 00:03:01,870 --> 00:03:05,020 So let's comment out these last two lines of code, 50 00:03:05,380 --> 00:03:10,380 and then let's take our sentence and let's say for word in sentence.split. 51 00:03:13,060 --> 00:03:17,560 And now let's print out each of the words. And when I run this, 52 00:03:17,590 --> 00:03:22,590 you can see it has split our entire sentence by the spaces to create a list of 53 00:03:23,590 --> 00:03:27,760 words. And each time it iterates through it using for word in sentence.split 54 00:03:27,790 --> 00:03:28,960 just like we have here, 55 00:03:29,260 --> 00:03:34,000 it's going to go through each word in turn and then check each of them. 56 00:03:34,720 --> 00:03:39,720 So now let's reactivate our code. And we wanna fix the very last part. 57 00:03:40,960 --> 00:03:44,590 So the new key is going to be the actual word 58 00:03:44,650 --> 00:03:49,650 because we want each of the words in our dictionary as the key, and the new value 59 00:03:49,690 --> 00:03:54,040 is going to be the length of the word. So now when I hit run, 60 00:03:54,100 --> 00:03:59,100 you can see we've got a dictionary where each word is the key and the number of 61 00:03:59,320 --> 00:04:02,200 characters in each word is the value. 62 00:04:02,920 --> 00:04:04,810 And now I've completed the challenge.