1 00:00:07,970 --> 00:00:10,875 So, let's go over some questions. 2 00:00:10,875 --> 00:00:13,710 So, this is a true false boolean. 3 00:00:13,710 --> 00:00:19,335 So, true false a dictionary is an unordered collection of key value pairs, 4 00:00:19,335 --> 00:00:21,960 that is absolutely true. 5 00:00:21,960 --> 00:00:24,615 That is what a dictionary is. 6 00:00:24,615 --> 00:00:27,075 Then we have a multiple choice. 7 00:00:27,075 --> 00:00:29,340 What's printed by the following statement. 8 00:00:29,340 --> 00:00:35,280 So, here we declare a dictionary with three key value pairs cat, dog, elephant. 9 00:00:35,280 --> 00:00:39,790 And then we print out my dictionary sub dog. 10 00:00:39,790 --> 00:00:43,055 So, the value of this expression is, 11 00:00:43,055 --> 00:00:48,350 whatever value is associated with the key dog in my dictionary. 12 00:00:48,350 --> 00:00:50,825 So, in order to answer this question, 13 00:00:50,825 --> 00:00:54,080 we have to look at what's associated with this key dog. 14 00:00:54,080 --> 00:00:57,335 We find the key value pair for dog here, 15 00:00:57,335 --> 00:01:01,445 and we see that the value associated with the key dog is six. 16 00:01:01,445 --> 00:01:05,250 So, we should expect six to be printed out. 17 00:01:07,070 --> 00:01:09,980 Then this question asks us to create 18 00:01:09,980 --> 00:01:13,415 a dictionary that keeps track of the USA's Olympic medal count. 19 00:01:13,415 --> 00:01:16,340 Each key of the dictionary should be the type of metal; 20 00:01:16,340 --> 00:01:19,010 so gold, silver or bronze, 21 00:01:19,010 --> 00:01:24,860 and each key's value should be the number of that type of metal that the USA has won. 22 00:01:24,860 --> 00:01:28,175 So currently, the US has 33 gold, 23 00:01:28,175 --> 00:01:32,065 17 silver and 12 bronze. 24 00:01:32,065 --> 00:01:35,715 So again, the keys here should be gold, silver and bronze, 25 00:01:35,715 --> 00:01:38,300 and the values associated with those keys should be 26 00:01:38,300 --> 00:01:41,705 the number of the medal that the US has won. 27 00:01:41,705 --> 00:01:46,975 Then they want us to create that dictionary and save it in the variable medals. 28 00:01:46,975 --> 00:01:48,930 So in the code, 29 00:01:48,930 --> 00:01:55,290 I'm going to say medals equals a dictionary. 30 00:01:55,290 --> 00:01:57,265 So, I'll use curly braces, 31 00:01:57,265 --> 00:02:03,110 and first I want to have the key gold associated with the value 33. 32 00:02:03,110 --> 00:02:07,760 If I just typed gold 33 which is common to do, 33 00:02:07,760 --> 00:02:09,925 then I would actually get an air, 34 00:02:09,925 --> 00:02:14,090 because when I say gold it's looking for your variable called gold. 35 00:02:14,090 --> 00:02:17,690 Instead I want to make this key a string. 36 00:02:17,690 --> 00:02:24,265 So, I want the string gold to be associated with the value integer 33. 37 00:02:24,265 --> 00:02:26,010 Same thing with silver. 38 00:02:26,010 --> 00:02:30,750 So, silver is associated with the value 17, 39 00:02:30,750 --> 00:02:36,090 and bronze is associated with the value 12. 40 00:02:36,090 --> 00:02:38,625 So, here I just got each of these. 41 00:02:38,625 --> 00:02:44,625 So, 12,17 and 33 from the problem statement. 42 00:02:44,625 --> 00:02:46,860 So, now when I run my code, 43 00:02:46,860 --> 00:02:49,690 then I should see that it parses. 44 00:02:51,290 --> 00:02:54,100 So, this question is very similar. 45 00:02:54,100 --> 00:02:56,680 Here we are told you're keeping track of Olympic medals 46 00:02:56,680 --> 00:02:59,740 for Italy in the 2016 Rio Summer Olympics. 47 00:02:59,740 --> 00:03:02,560 At the moment Italy has seven gold, 48 00:03:02,560 --> 00:03:06,400 eight silver and six bronze metals. 49 00:03:06,400 --> 00:03:10,540 Create a dictionary called Olympics where the keys are the type of 50 00:03:10,540 --> 00:03:15,640 medal and the values are the number of that type of medal that Italy has won so far. 51 00:03:15,640 --> 00:03:17,335 So, exact same idea, 52 00:03:17,335 --> 00:03:20,590 I'm going to say Olympics equals, 53 00:03:21,360 --> 00:03:24,280 and then we want to assign that to be a dictionary, 54 00:03:24,280 --> 00:03:25,720 so, we use curly braces. 55 00:03:25,720 --> 00:03:27,790 We have three key-value pairs. 56 00:03:27,790 --> 00:03:33,945 So, we have gold associated with the value seven, 57 00:03:33,945 --> 00:03:37,100 then just for the sake of writing this out slightly differently, 58 00:03:37,100 --> 00:03:46,330 I'm going to set silver on the next line by saying Olympics sub silver equals eight. 59 00:03:46,330 --> 00:03:52,745 So, this is going to add a new key value pair associating silver with the value eight. 60 00:03:52,745 --> 00:04:03,025 And then I need to also say Olympics sub bronze equals six. 61 00:04:03,025 --> 00:04:05,990 So, here I just did something slightly different, 62 00:04:05,990 --> 00:04:10,820 I could have added three value pairs right in here like I did for the previous problem, 63 00:04:10,820 --> 00:04:14,660 but I could also just set the key value pairs using 64 00:04:14,660 --> 00:04:19,445 an assignment statement like I did on lines two or on lines three. 65 00:04:19,445 --> 00:04:21,695 Again, the keys are all strings, 66 00:04:21,695 --> 00:04:24,290 so here I'm using double quotes to create the string, 67 00:04:24,290 --> 00:04:25,880 here I'm using single quotes, 68 00:04:25,880 --> 00:04:28,915 but the effect is that we have three key-value pairs, 69 00:04:28,915 --> 00:04:30,405 all the keys are strings. 70 00:04:30,405 --> 00:04:31,940 So, gold, silver and bronze. 71 00:04:31,940 --> 00:04:36,660 All the values are integers seven, eight and six. 72 00:04:37,990 --> 00:04:41,820 That's all for now until next time.