1 00:00:01,620 --> 00:00:02,580 Hey, welcome back. 2 00:00:03,360 --> 00:00:09,030 As you have noticed, through all the calls, we have been doing two main things, which is adding new 3 00:00:09,030 --> 00:00:13,200 features and then improving the user experience. 4 00:00:13,530 --> 00:00:20,970 So these are two phases that you have to go through over the lifecycle, the development lifecycle of 5 00:00:20,970 --> 00:00:21,960 your program. 6 00:00:22,950 --> 00:00:27,540 And in this video, we will be improving the user experience again. 7 00:00:27,840 --> 00:00:30,500 What exactly will be doing is this? 8 00:00:30,510 --> 00:00:37,770 So let's say the user is adding new to DOS in order to do list, and I show that to dos and they want 9 00:00:37,770 --> 00:00:39,180 to add it to something. 10 00:00:39,480 --> 00:00:46,590 But in order to say what they want to add it, they want to they have to count currently 1 to 3 and 11 00:00:46,590 --> 00:00:48,390 maybe they decide on number three. 12 00:00:48,390 --> 00:00:49,630 So they enter three there. 13 00:00:49,650 --> 00:00:52,840 So we want to make this experience flawless. 14 00:00:52,860 --> 00:01:00,090 We want to show numbers in front of each to do so that the user can simply look at the number and then 15 00:01:00,090 --> 00:01:03,270 write the number there so they don't have to count. 16 00:01:03,900 --> 00:01:05,280 How do we do that? 17 00:01:05,519 --> 00:01:06,270 Well. 18 00:01:08,680 --> 00:01:15,040 We have to look at where we are printing out those items, which is in here. 19 00:01:15,250 --> 00:01:18,010 So we produce that list. 20 00:01:18,890 --> 00:01:20,630 Using this for loop. 21 00:01:20,630 --> 00:01:24,920 The for loop goes over to to dos and prints out its each item. 22 00:01:25,340 --> 00:01:30,890 Now the solution to show numbers in front is the enumerate function. 23 00:01:30,920 --> 00:01:33,620 Let me demonstrate to you what enumerate is. 24 00:01:33,620 --> 00:01:43,100 So let's say we have to do list currently, which is let's say, clean through and do that. 25 00:01:43,100 --> 00:01:44,690 At least we have this point. 26 00:01:44,690 --> 00:01:47,090 So we have we have that list in here. 27 00:01:47,090 --> 00:01:48,170 We want to show that. 28 00:01:48,170 --> 00:01:53,300 So currently what we do is for item into dos print item. 29 00:01:55,550 --> 00:01:56,080 Right. 30 00:01:56,090 --> 00:01:57,950 We execute and we get the list. 31 00:01:57,980 --> 00:02:05,960 Now, what we want to do is we want to go back in here and say Enumerate, which is a function. 32 00:02:05,960 --> 00:02:09,530 And this function gets as inputs a list. 33 00:02:09,949 --> 00:02:18,560 So the list goes as the inputs of enumerate, function and enumerate function now makes available not 34 00:02:18,560 --> 00:02:23,090 only the items of the list, but also the indices of that list. 35 00:02:23,820 --> 00:02:26,460 So we're going to get two elements from here. 36 00:02:26,460 --> 00:02:37,620 Therefore, we need two variables for eye or index for index and item in enumerate to dos print item, 37 00:02:38,580 --> 00:02:40,380 and we also print index. 38 00:02:40,890 --> 00:02:44,880 So index and item to go down here, press enter. 39 00:02:45,570 --> 00:02:47,340 And so this is what we get. 40 00:02:49,670 --> 00:02:57,230 So what's happened is that we print out the index in the first iteration and also the item. 41 00:02:57,230 --> 00:03:05,150 So in the first iteration, the full loop goes and gets it gets clean and it's index zero. 42 00:03:05,150 --> 00:03:10,400 So it stores clean in the item variable and zero in the index variable. 43 00:03:10,490 --> 00:03:14,750 And therefore and here we print out zero and clean. 44 00:03:15,140 --> 00:03:18,200 It does the same for the other indexes and other items. 45 00:03:19,310 --> 00:03:25,190 So let's go back to our code now and implement the same enumerate function. 46 00:03:25,190 --> 00:03:39,530 So for index item in enumerate to do's print index item if you want, you can also add a third argument 47 00:03:39,560 --> 00:03:43,010 in between here, which could be a string. 48 00:03:43,040 --> 00:03:53,090 Single quotes should be enough dot perhaps, or a dash, whatever you like and let's see what we will 49 00:03:53,090 --> 00:03:53,750 get. 50 00:03:53,780 --> 00:03:56,840 So run, stop and rerun. 51 00:03:56,840 --> 00:04:02,150 Add through, add, do show. 52 00:04:02,870 --> 00:04:04,400 Yep, that's what we get. 53 00:04:05,690 --> 00:04:07,250 So it's looking better. 54 00:04:07,610 --> 00:04:09,290 Not ideal though. 55 00:04:09,470 --> 00:04:16,940 I would prefer not to have these spaces or at least the space between the dash and through. 56 00:04:18,010 --> 00:04:20,990 So how can we change the format of this text? 57 00:04:21,010 --> 00:04:23,170 How can we remove that space? 58 00:04:24,220 --> 00:04:24,640 Here. 59 00:04:24,640 --> 00:04:33,490 We don't seem to have any spaces, so we don't have much control over this thing when we use this sprint 60 00:04:33,490 --> 00:04:34,240 function. 61 00:04:34,540 --> 00:04:39,130 But we can get control over that if we use F strings. 62 00:04:39,340 --> 00:04:42,580 F strings is something we're going to be using in the next video. 63 00:04:42,580 --> 00:04:43,750 So I'll talk to you there.