WEBVTT 00:00.200 --> 00:00.860 Hello guys. 00:00.860 --> 00:03.320 So we are going to continue our discussion with respect to Python. 00:03.320 --> 00:06.350 And now we are going to start data structures in Python. 00:06.350 --> 00:11.540 Some of the most common data structures that are used in Python programming language are like lists, 00:11.570 --> 00:13.310 tuples, sets and dictionaries. 00:13.310 --> 00:17.210 So in this series of videos, we are probably going to discuss about all these topics. 00:17.210 --> 00:19.820 In this video we are going to focus more on list. 00:20.090 --> 00:23.600 Uh, so let me just go ahead and show you what is the video outline. 00:23.600 --> 00:28.820 So first of all, we will, uh, go ahead and show you how to I will go ahead and show you how to create 00:28.820 --> 00:29.330 a list. 00:29.330 --> 00:35.270 Then I will also show you accessing list items, modifying list items, some of the amazing list methods 00:35.270 --> 00:36.110 that we use. 00:36.140 --> 00:38.960 Then we have operations like slicing list. 00:39.050 --> 00:41.510 How do I how do we iterate over list? 00:41.540 --> 00:43.220 You know by using for loop and all. 00:43.250 --> 00:46.580 Then along with that we'll also be seeing list comprehension. 00:46.580 --> 00:48.950 And then we will be seeing about nested list. 00:48.950 --> 00:52.100 All these things will be covered with lot of practical examples. 00:52.100 --> 00:55.610 And I'll also be talking about what are the common errors that we will be getting. 00:55.610 --> 01:00.390 So before I go ahead, first of all, let us go ahead and just see the definition of list. 01:00.390 --> 01:05.340 So here you can see list are ordered mutable collection of items right. 01:05.370 --> 01:07.170 Ordered mutable collection of items. 01:07.170 --> 01:09.570 What does mutable collection of items basically means? 01:09.720 --> 01:13.500 Like all the items that are present in list, we can actually change it. 01:13.530 --> 01:14.160 Okay. 01:14.280 --> 01:18.600 Um, and they can contain items of different data types also. 01:18.600 --> 01:18.870 Right. 01:18.870 --> 01:22.530 So these are the two main proper properties with respect to list. 01:22.590 --> 01:25.170 Uh, first of all, they are ordered mutable collection of items. 01:25.170 --> 01:28.410 And they can contain items of different different data types. 01:28.410 --> 01:30.480 So let me just go ahead and let me show you that. 01:30.510 --> 01:32.190 How do you define a list? 01:32.220 --> 01:34.710 Let's say I create a variable called as list. 01:34.920 --> 01:37.080 And if I use this two brackets. 01:37.080 --> 01:40.020 And before that don't forget to select a kernel. 01:40.020 --> 01:43.860 So right now I have selected the kernel based on the environment that I've actually created. 01:43.860 --> 01:49.980 So here you can see over here when I write list with some this empty square braces. 01:49.980 --> 01:57.930 And if I go ahead and print the type of this variable this will give us an empty list. 01:57.960 --> 01:58.260 Right. 01:58.260 --> 02:00.870 So this is a class type of list. 02:00.870 --> 02:03.450 So in order to create a list it is very much simple. 02:03.450 --> 02:06.720 You can just use this empty brackets right. 02:06.960 --> 02:12.600 Um now if I want to add elements in the list, uh, let's say that I want to go ahead and create it. 02:12.630 --> 02:15.210 Like I may have multiple names over here. 02:15.210 --> 02:23.940 Let's say I have Croatia, I have, um, Jack, I have Jacob. 02:23.940 --> 02:24.360 Right. 02:24.360 --> 02:26.640 So this is basically a list of names. 02:26.670 --> 02:27.150 Okay. 02:27.180 --> 02:33.180 I may also have other elements like I may have one, two, three, four, five, any number of elements. 02:33.180 --> 02:36.210 I may also have different different data types of elements over here. 02:36.240 --> 02:40.050 So here if I go ahead and go ahead and print names. 02:40.650 --> 02:44.310 So it is giving me a name error because I did not write names. 02:44.310 --> 02:47.700 So here you can see that I'm able to get a list of elements right. 02:47.700 --> 02:49.530 So this is how a list is. 02:49.560 --> 02:52.440 Let's say that I go ahead and create a mixed list. 02:52.470 --> 02:55.320 Mixed underscore list list. 02:55.320 --> 02:57.970 And here let's say my first is a number. 02:58.000 --> 03:00.310 Second is a string. 03:00.340 --> 03:02.770 Third is a floating point right. 03:02.770 --> 03:04.450 And fourth is a Boolean variable. 03:04.480 --> 03:04.900 Right. 03:04.930 --> 03:07.270 So I may define any types of data type. 03:07.270 --> 03:08.740 And I may also print this. 03:08.740 --> 03:12.730 So let me just go ahead and print mixed underscore list. 03:12.730 --> 03:16.750 So I hope you got an idea about how to probably create a list of items right. 03:16.780 --> 03:21.100 So one is directly we are using this particular empty brackets. 03:21.100 --> 03:23.920 Or you can also go ahead and add elements over here. 03:24.190 --> 03:28.930 Um with respect to and any, any kind of elements, any different different data types of elements you 03:28.930 --> 03:29.860 can basically add. 03:29.890 --> 03:30.370 Okay. 03:30.400 --> 03:36.550 Now let's talk about accessing accessing list items. 03:36.550 --> 03:39.550 How do we access the list elements. 03:39.580 --> 03:40.060 Right. 03:40.060 --> 03:43.630 So let's say that I uh I create a fruits right. 03:43.630 --> 03:47.590 Let's say that I'm going to create a fruits element like a list of fruits. 03:47.590 --> 03:49.270 Let's say like apple. 03:49.270 --> 03:51.610 It can be banana. 03:51.640 --> 04:00.620 It can be cherry It can be, um, Kiwi. 04:00.860 --> 04:06.350 It can be, um, pomegranate. 04:06.380 --> 04:06.980 Okay. 04:07.520 --> 04:10.010 Or let me just write a simple, uh. 04:10.040 --> 04:10.340 Okay. 04:10.340 --> 04:11.570 Let's go ahead and see. 04:11.570 --> 04:13.340 Uh, cherry is already written. 04:13.550 --> 04:14.540 Um, Apple. 04:14.570 --> 04:15.440 Banana, cherry. 04:15.710 --> 04:16.370 Kiwi. 04:16.880 --> 04:17.840 Um, okay. 04:17.840 --> 04:20.570 I, I'm not able to remember more fruits names. 04:20.570 --> 04:21.140 Right. 04:21.320 --> 04:23.930 So let's just keep it till here, okay. 04:24.230 --> 04:24.590 Or. 04:24.590 --> 04:25.520 Okay, fine. 04:25.550 --> 04:27.770 I finally I got one guava. 04:27.770 --> 04:28.430 Right. 04:28.430 --> 04:31.550 So I'm just going to go ahead and create this list of elements. 04:31.550 --> 04:33.800 So here is my list of elements over here. 04:33.830 --> 04:38.240 Now uh, let's say that I want to go ahead and display Apple right. 04:38.240 --> 04:42.860 So in order to display it all I have to do is that just go ahead and right roots fruits. 04:42.860 --> 04:46.520 And here you can probably see that I can actually use indexing. 04:46.550 --> 04:46.970 Right. 04:46.970 --> 04:50.990 So whenever we create the elements inside a list okay. 04:50.990 --> 04:56.610 So here this first fruit is basically present in the zeroth index, then this is present in the first 04:56.610 --> 04:56.910 index. 04:56.910 --> 04:57.480 Second index. 04:57.480 --> 04:58.020 Third index. 04:58.020 --> 04:58.770 Fourth index. 04:58.770 --> 05:04.530 So similarly all the indexes uh, when I probably say all the indexes in Python starts with zero. 05:04.560 --> 05:09.150 If you know about R programming language, all the indexes over there starts with one number one. 05:09.150 --> 05:09.450 Right. 05:09.450 --> 05:14.130 But here we are specifically going to use um zero is the index over here. 05:14.160 --> 05:14.550 Right. 05:14.550 --> 05:18.300 But uh if I really want to just display Apple right. 05:18.300 --> 05:21.090 So I will just go ahead and write fruit of zero. 05:21.090 --> 05:21.390 Right. 05:21.390 --> 05:23.400 If I'm actually trying to print this. 05:23.400 --> 05:26.310 So let me just go ahead and write print Fruits of zero. 05:26.310 --> 05:28.170 It is not nothing but apple. 05:28.170 --> 05:33.720 Let's say I want to probably get fruit of uh, um in middle cherry. 05:33.750 --> 05:34.020 Right. 05:34.050 --> 05:35.730 So this will become 012. 05:35.760 --> 05:39.960 So if I go ahead and write fruits of two. 05:39.990 --> 05:42.090 So I will be able to get apple and cherry. 05:42.090 --> 05:45.960 And there are some amazing techniques with respect to indexing also. 05:45.960 --> 05:48.750 So let's say that I want to pick up guava right. 05:48.750 --> 05:50.970 So I can also go ahead and write print. 05:51.240 --> 05:51.900 Um, yeah. 05:51.930 --> 05:55.710 One way is that I can go ahead and take one zero, one two, three four. 05:55.710 --> 05:59.550 So I can probably go ahead and write fruits of fourth index. 05:59.550 --> 06:00.810 I will be able to get guava. 06:00.840 --> 06:04.380 Now this guava can also be taken through a different way. 06:04.380 --> 06:05.700 So let me just go ahead and write. 06:05.700 --> 06:10.020 So let's say that I'm going to write print of all fruits. 06:10.590 --> 06:14.520 Let me just say and show it to you over here. 06:14.520 --> 06:20.340 So let me just go ahead and write fruits of Fruits of okay. 06:20.340 --> 06:23.160 And now in this particular case let me just go ahead and write minus one. 06:23.160 --> 06:24.000 Let's see what will happen. 06:24.030 --> 06:27.750 See minus one is nothing, but it is basically talking about the last element itself. 06:27.750 --> 06:28.020 Right. 06:28.020 --> 06:30.210 So I think I should be able to get both guava. 06:30.240 --> 06:30.690 Right. 06:30.690 --> 06:34.050 So this is the amazing thing with respect to fruits, right. 06:34.140 --> 06:34.920 Uh, sorry. 06:34.920 --> 06:35.850 This list. 06:35.880 --> 06:36.180 Right. 06:36.180 --> 06:41.790 You are able to probably retrieve any fruit or any items inside this list just by using simple indexing. 06:41.820 --> 06:47.460 Okay, now let me just show you one more way of printing some set of fruits elements. 06:47.460 --> 06:49.950 So if I go ahead and write fruits okay. 06:49.950 --> 06:55.990 And you know, if I just use the index one okay, I'll be able to get banana. 06:55.990 --> 06:58.870 So I'm getting banana zero one I'm getting banana over here. 06:58.870 --> 07:00.580 But what if I have a requirement? 07:00.580 --> 07:03.310 I need to get all the elements from banana till guava. 07:03.340 --> 07:03.820 Right. 07:03.820 --> 07:08.320 So if I go ahead and just make one simple change over here, right. 07:08.350 --> 07:11.590 What I will do, I'll say write fruits one colon. 07:11.590 --> 07:11.950 Right? 07:11.950 --> 07:18.310 One colon basically means from one first index till the end index because I'm not giving anything after 07:18.310 --> 07:18.820 the colon. 07:18.820 --> 07:23.950 So if I just go ahead and execute this here you can see banana cherry kiwi guava right. 07:23.950 --> 07:26.470 So this is one way right now let me do one thing. 07:26.500 --> 07:31.630 Let me just go ahead and print fruits one colon. 07:31.630 --> 07:36.040 And let's say I want to get all the elements till this kiwi index one. 07:36.190 --> 07:37.870 So here you have zero one. 07:37.870 --> 07:39.370 So right two three. 07:39.400 --> 07:39.610 Right. 07:39.640 --> 07:43.930 So now if I go ahead and write one colon three, that basically means it is just going to pick up this 07:43.930 --> 07:44.410 first index. 07:44.410 --> 07:46.720 Second index it is not going to pick up the Kiwi index. 07:46.720 --> 07:47.230 Right. 07:47.500 --> 07:49.670 Uh and now if I go ahead and display it. 07:49.670 --> 07:51.590 So here you can see banana and cherries there. 07:51.620 --> 07:56.090 That basically means the third index is not getting picked up till the third index everything will get 07:56.090 --> 07:56.990 picked up right. 07:57.020 --> 08:01.580 So if I don't write any element over here, so it is just going to take it completely till the end. 08:01.610 --> 08:02.180 Right. 08:02.180 --> 08:07.490 And uh, here also what I can actually do, let me just go ahead and show you one more thing. 08:07.490 --> 08:12.260 So if I go ahead and write print of fruits, uh, minus one colon. 08:12.290 --> 08:12.620 Right. 08:12.650 --> 08:17.480 Now, if I go ahead and execute this, you can see minus one colon basically means from minus one element 08:17.510 --> 08:18.260 till colon. 08:18.260 --> 08:18.470 Right. 08:18.500 --> 08:19.850 Till colon means till the end. 08:19.850 --> 08:22.580 And this is just my last element over there okay. 08:22.580 --> 08:28.670 But if I just go ahead and write -1 or 2 let's say second index. 08:28.670 --> 08:35.450 So here I can see that you have to please observe over here minus one is nothing but this specific element 08:35.450 --> 08:35.930 right. 08:35.960 --> 08:38.000 Two is this right. 08:38.000 --> 08:40.100 But I'm not talking about all these elements. 08:40.130 --> 08:44.900 Now if I go ahead and write minus one to -3 or -3 right. 08:44.930 --> 08:50.730 Now here also you'll be able to see this indexing Thing is obviously a little bit confusion. 08:50.730 --> 08:51.120 Okay. 08:51.150 --> 08:55.320 There is a little bit of confusion over here because when I'm picking up the minus one element, this 08:55.320 --> 08:56.310 is it is giving us. 08:56.310 --> 08:58.530 But I'm saying from -1 to -3. 08:58.560 --> 08:58.920 Right. 08:58.920 --> 09:00.360 So there is no such element. 09:00.360 --> 09:04.440 And we'll talk more about this kind of examples and how to do this kind of indexing. 09:04.440 --> 09:07.800 Also when we are further discussing about many things as such. 09:07.830 --> 09:08.130 Right. 09:08.160 --> 09:09.720 Right now don't worry about this. 09:09.720 --> 09:11.760 Otherwise you'll get more confused over here. 09:11.910 --> 09:13.950 Uh, I'll just keep it like this. 09:13.950 --> 09:18.930 I'll remove this particular code for some time, and then later on when you'll see in the series of 09:18.930 --> 09:21.330 videos, we'll also be talking about those kind of indexing. 09:21.360 --> 09:21.840 Okay. 09:21.870 --> 09:22.980 Now perfect. 09:23.010 --> 09:23.490 Till here. 09:23.490 --> 09:26.910 I think uh, we have, uh, learnt many things over here. 09:26.940 --> 09:30.600 Now, what I will be showing you is that how you can modify the list elements. 09:30.630 --> 09:31.050 Okay. 09:31.050 --> 09:36.900 So let me just go ahead here and show you modifying the list elements okay. 09:36.930 --> 09:39.960 Now modifying the list elements is very simple. 09:39.960 --> 09:42.690 Let's say that I want this is my fruits right. 09:42.690 --> 09:43.950 So this is my fruits. 09:43.950 --> 09:47.190 I want to make sure that I replace banana with something else. 09:47.220 --> 09:48.210 Right now. 09:48.210 --> 09:48.720 Banana. 09:48.750 --> 09:49.620 You know it. 09:49.620 --> 09:50.910 It is in first index. 09:50.940 --> 09:51.120 Right. 09:51.120 --> 09:53.430 So if I go ahead and write this it is in first index. 09:53.430 --> 09:57.960 Let's say from this I want to probably change this into watermelon okay. 09:58.320 --> 10:01.920 And now I will just go ahead and print my fruits. 10:01.950 --> 10:02.430 Right. 10:02.430 --> 10:07.260 So in that specific index I am writing watermelon over here and I'm actually displaying it. 10:07.260 --> 10:12.330 Now you can see my fruits has changed banana to uh to watermelon right. 10:12.330 --> 10:18.840 So this way in the indexing also you can directly go ahead and probably replace this particular values. 10:18.840 --> 10:19.230 Right. 10:19.230 --> 10:24.270 So this is how you modify uh any elements that is present over here. 10:24.300 --> 10:27.990 Not only that, let's say I want to go ahead and write like this. 10:27.990 --> 10:30.150 Fruits okay. 10:30.180 --> 10:32.640 Fruits one colon okay. 10:32.640 --> 10:34.830 So one colon is basically giving you this answer. 10:34.860 --> 10:39.300 Now if I go ahead and just write here, please replace everything with watermelon. 10:39.330 --> 10:41.490 Now if I go ahead and see fruits. 10:41.640 --> 10:45.790 So here you can see uh I'm getting this error or. 10:45.820 --> 10:47.560 Let's see what is the problem. 10:47.710 --> 10:48.940 Watermelon okay. 10:48.970 --> 10:54.040 Now what it has done is that from this particular index, from this particular index it has replaced 10:54.070 --> 10:55.810 with this particular word. 10:55.840 --> 10:56.290 Right. 10:56.290 --> 10:59.050 But here it is not considered as a word. 10:59.050 --> 11:01.660 Instead it is taking this as character by character. 11:01.690 --> 11:05.020 We will also be seeing how we can add word to word. 11:05.050 --> 11:05.470 Right. 11:05.470 --> 11:10.060 So in in in in list you have some amazing methods like append and all. 11:10.060 --> 11:12.730 We will be talking about it as we go ahead right now okay. 11:12.760 --> 11:14.620 Just after this section itself. 11:14.650 --> 11:14.950 Right. 11:14.950 --> 11:17.710 So this is one of the problem that we see right now. 11:17.710 --> 11:18.550 Let me do one thing. 11:18.550 --> 11:22.900 Let me again use that same fruits over here that I've actually defined. 11:23.080 --> 11:23.560 Okay. 11:23.560 --> 11:25.090 But you understood the problem. 11:25.090 --> 11:27.940 What has happened over here as soon as I said one colon. 11:27.970 --> 11:28.180 Right. 11:28.210 --> 11:31.900 So from first index it has just added w a t r. 11:31.930 --> 11:34.630 So it is not just considered this as a single word. 11:34.630 --> 11:37.450 Instead it is considering character by character and it is adding it. 11:37.450 --> 11:40.060 Okay, so let me just go ahead and define my fruits again. 11:40.090 --> 11:40.540 Okay. 11:40.570 --> 11:47.280 Now let me just go ahead and discuss more about amazing thing that is called as list methods. 11:47.310 --> 11:50.910 Okay, now this list methods is quite beautiful. 11:50.910 --> 11:53.610 We will see to it and we'll be learning more about it. 11:53.640 --> 11:56.730 Okay, now let's say I want to, as I said right. 11:56.730 --> 12:02.070 I want to append an element inside this okay I want to add one element at the end let's say. 12:02.070 --> 12:05.400 So for this I will go ahead and write fruits dot append. 12:05.400 --> 12:09.030 And here let's say I want to append orange okay. 12:09.090 --> 12:16.500 Now once I write that basically means this will add an item okay to the end okay. 12:16.770 --> 12:19.620 It will basically add an item to the end okay. 12:19.650 --> 12:25.320 And if I just go ahead and print my fruits you will be able to see this. 12:25.320 --> 12:25.680 Right. 12:25.680 --> 12:31.260 So now here we'll be able to see apple banana cherry kiwi guava and oranges over here. 12:31.290 --> 12:31.830 Right. 12:32.430 --> 12:39.330 Now let's say that I have a requirement that I want to probably append any element at a specific index. 12:39.360 --> 12:39.780 Okay. 12:39.810 --> 12:49.200 So let's say I want to add, um, let's say I want to add watermelon in this first index. 12:49.800 --> 12:50.010 Okay. 12:50.010 --> 12:51.930 And right now in the first index banana is there. 12:51.930 --> 12:57.210 So what I will do I'll say fruits dot insert okay insert. 12:57.330 --> 12:59.100 And I will give the index number. 12:59.130 --> 13:00.870 The first element will be the index number. 13:00.870 --> 13:05.760 And the second element will be whatever item I want to put let's say banana okay. 13:05.760 --> 13:09.150 And then I'm just going to print fruits. 13:10.500 --> 13:13.350 So here you can see apple banana banana okay. 13:13.380 --> 13:15.300 Banana was already there I guess. 13:15.480 --> 13:16.920 Yeah banana was there. 13:16.920 --> 13:18.150 Let me do one thing. 13:18.150 --> 13:21.390 Let me add watermelon also. 13:21.420 --> 13:21.630 Okay. 13:21.660 --> 13:24.300 So in the first index I'm just going to add watermelon. 13:24.300 --> 13:29.520 So here you can see apple watermelon banana banana banana because I have added one time right. 13:29.550 --> 13:31.830 Let's say that I hate two bananas are there. 13:31.830 --> 13:32.820 I want to remove this. 13:32.820 --> 13:35.400 So I will go ahead and write fruits dot remove. 13:35.400 --> 13:39.150 So remove is another inbuilt function uh that is present inside this. 13:39.150 --> 13:40.620 So here I'm going to basically write right. 13:40.650 --> 13:41.280 Banana. 13:41.400 --> 13:41.820 Okay. 13:41.850 --> 13:45.570 And now if I go ahead and print fruits. 13:45.600 --> 13:46.020 Okay. 13:46.050 --> 13:48.840 So here you can see banana has gone right now. 13:48.840 --> 13:51.000 But we don't have one more additional banana. 13:51.030 --> 13:51.810 Okay. 13:52.320 --> 14:03.330 Uh, let's say I want to also remove and, um, let's say, uh, see, whenever we are using this remove. 14:03.360 --> 14:03.750 Right. 14:03.750 --> 14:13.500 It is basically removing the first occurrence of an item. 14:13.530 --> 14:14.220 Right. 14:14.520 --> 14:19.140 Now let's say I want to remove and return the last item. 14:20.640 --> 14:22.860 Return the last item. 14:24.360 --> 14:24.960 Okay. 14:26.430 --> 14:28.350 Let's say I want to do this. 14:28.650 --> 14:30.660 Uh, what do I mean by this? 14:30.660 --> 14:35.070 Let's say I go ahead and use one amazing inbuilt function which is called as pop. 14:35.100 --> 14:35.670 Okay. 14:35.820 --> 14:42.340 Now pop basically means it is just going to pop the last element that is present in that particular 14:42.340 --> 14:44.800 fruit, and it is going to return us. 14:44.830 --> 14:45.010 Right. 14:45.040 --> 14:49.630 So here I'm going to write popped underscore fruit okay. 14:49.660 --> 14:50.560 Is equal to. 14:50.590 --> 14:52.840 And let me just go ahead and print it. 14:52.840 --> 14:54.580 So I'm going to print it over here. 14:54.580 --> 14:58.000 And let me just go ahead and write pop fruits okay. 14:58.030 --> 15:00.820 And uh let me just print it okay. 15:00.850 --> 15:07.210 Let's uh because at the end of the day, once, I probably, uh, print this and I'll also print the 15:07.210 --> 15:09.610 remaining items that are there in the fruits. 15:09.940 --> 15:10.390 Okay. 15:10.420 --> 15:12.520 So here you can see orange has been popped. 15:12.520 --> 15:12.880 Why? 15:12.910 --> 15:16.870 Because the last element in this list of fruits was orange. 15:16.870 --> 15:20.470 When orange was popped from this particular orange got removed. 15:20.500 --> 15:23.620 Okay, remove and return the last element. 15:24.040 --> 15:25.840 That is how you can specifically do it. 15:25.840 --> 15:28.600 And for that we use an inbuilt function called as pop. 15:28.630 --> 15:36.190 Okay, now let's say that I want to get an index of any fruit right based on the name of the fruit. 15:36.190 --> 15:39.410 So if I go ahead and write fruits dot index. 15:39.410 --> 15:43.460 And here let's say that I want to use cherry. 15:43.730 --> 15:48.800 I want to get the index of the fruit called as cherry okay cherry. 15:48.830 --> 15:51.290 And this will basically be my index. 15:52.400 --> 15:55.700 And let me just go ahead and print the index. 15:57.020 --> 16:02.930 Now if I go ahead and execute, you can see that cherry is basically present in 012 three third index. 16:02.930 --> 16:04.820 So I am able to get the output. 16:04.850 --> 16:05.390 Okay. 16:05.840 --> 16:13.160 Uh, again one more thing is that let me just go ahead and do one thing fruit dot append or I will try 16:13.190 --> 16:16.790 to insert in the second index. 16:16.970 --> 16:18.590 Banana okay. 16:19.100 --> 16:20.690 Banana is already there. 16:20.720 --> 16:24.320 And now let me do one one more inbuilt function. 16:24.320 --> 16:26.660 I will just go ahead and write fruit dot count. 16:26.810 --> 16:28.820 And here I will just go ahead and write. 16:28.850 --> 16:30.380 Sorry, it should be count. 16:30.470 --> 16:34.400 I will just go ahead and write banana okay. 16:34.610 --> 16:37.470 And let me just print this. 16:37.500 --> 16:38.070 Okay. 16:38.640 --> 16:43.860 Now, what is going to happen is that you'll be able to see it'll just count the number of elements. 16:43.860 --> 16:50.100 And obviously, after inserting this banana right now, if you see inside my fruits there are two bananas, 16:50.100 --> 16:50.340 right? 16:50.430 --> 16:51.600 Banana and banana. 16:51.600 --> 16:52.890 So it is just counting that. 16:52.890 --> 16:57.300 How many number of items this specific uh, in this particular list it is there. 16:57.330 --> 16:57.900 Right. 16:58.290 --> 17:04.260 So here I'm just showing you different, different inbuilt function just by using a list of items. 17:04.260 --> 17:08.370 And here you can see I've shown you a lot of coding with respect to this okay. 17:08.910 --> 17:11.370 Now I may also do something like this. 17:11.370 --> 17:13.440 I may sort this entire list of items. 17:13.440 --> 17:16.230 So if I go ahead and write fruits dot sort. 17:16.980 --> 17:18.600 So here you'll be able to see. 17:18.630 --> 17:23.100 Now if I go ahead and print this fruits you'll be seeing apple banana. 17:23.130 --> 17:23.490 Banana. 17:23.490 --> 17:23.820 Cherry. 17:23.850 --> 17:24.180 Guava. 17:24.210 --> 17:24.510 Kiwi. 17:24.600 --> 17:25.380 Watermelon. 17:26.040 --> 17:36.690 So automatically based on so in in short this will this will sort the list in ascending order. 17:37.020 --> 17:37.410 Okay. 17:37.440 --> 17:39.930 It is just going to sort all the lists in ascending order. 17:39.960 --> 17:42.780 And finally here you have fruits dot reverse. 17:42.810 --> 17:46.860 Reverse is another function which will reverse all the elements over here. 17:46.890 --> 17:52.290 Now if I go ahead and do this right now you can see the all the list of the elements will basically 17:52.290 --> 17:53.430 get reversed right. 17:53.460 --> 17:59.310 So this is nothing, but it reverses the list okay. 17:59.370 --> 18:04.770 And just I'm showing you what all different different inbuilt functions are basically present over here. 18:04.800 --> 18:05.310 Okay. 18:05.310 --> 18:11.760 And then finally if I want to clear the entire list I can go ahead and write fruits dot clear. 18:12.000 --> 18:12.450 Right. 18:12.480 --> 18:15.570 And now if I use this inbuilt function. 18:15.570 --> 18:22.770 So this will remove all items from the list okay. 18:22.800 --> 18:25.530 Now if I go ahead and print fruits. 18:26.460 --> 18:29.040 So here you can see I'm getting an empty list. 18:29.040 --> 18:34.580 So till now we have discussed about mainly uh if, if I go ahead and show you with respect to the video, 18:35.630 --> 18:40.100 we have understood about creating list, accessing list items, modifying list elements. 18:40.370 --> 18:42.230 Uh, then we discussed about list methods. 18:42.230 --> 18:44.780 Now we are going to discuss about slicing list. 18:44.780 --> 18:48.170 So let's go ahead and discuss more about slicing list. 18:50.390 --> 18:53.630 So guys now let's go ahead and talk more about slicing list. 18:53.630 --> 18:57.050 So before that I will go ahead and make some cells. 18:57.050 --> 18:58.880 Uh so there is a shortcut. 18:58.880 --> 19:04.100 Just press escape and a you will be able to create as many number of cells as you want. 19:04.130 --> 19:04.610 Okay. 19:04.640 --> 19:10.340 Now what I'm actually going to do is that I am just going to take this numbers. 19:10.370 --> 19:10.580 Okay. 19:10.580 --> 19:14.300 So I'm defining these numbers 123456789 ten. 19:14.300 --> 19:17.900 Now I will just go ahead and write some print elements. 19:17.900 --> 19:23.360 Let's say print numbers two colon five okay. 19:23.690 --> 19:28.550 Now let's talk about more numbers. 19:30.140 --> 19:30.860 Oops. 19:34.490 --> 19:35.750 Colon five. 19:35.780 --> 19:37.730 Okay, okay. 19:37.730 --> 19:41.390 I didn't close this brackets, so that is the reason it was giving me an error. 19:41.420 --> 19:42.530 No worries. 19:43.580 --> 19:48.620 Now I will go ahead and write print numbers five colon. 19:48.770 --> 19:54.260 And along with this we will also go ahead and see print numbers. 19:55.700 --> 19:57.320 Double colon two. 19:57.350 --> 19:57.950 Okay. 19:58.670 --> 19:59.750 Double colon. 19:59.750 --> 20:01.640 So here we are also learning about double colon. 20:01.670 --> 20:03.950 Single colon I have just given you an idea about it. 20:03.950 --> 20:05.930 But we'll also see with respect to double colon. 20:05.930 --> 20:10.130 And then we'll also go ahead and print our numbers. 20:11.420 --> 20:13.850 Double colon minus one. 20:13.880 --> 20:14.390 Okay. 20:14.420 --> 20:21.560 Now just pause for a second and just try to imagine in your mind like what will be the specific outputs 20:21.590 --> 20:22.100 okay. 20:22.100 --> 20:23.840 And then we will discuss further. 20:23.870 --> 20:24.410 Okay. 20:24.440 --> 20:26.390 So here you can see two colon five. 20:26.420 --> 20:35.450 It is very simple 012 from 2 to 5 elements of Three, four, five is basically getting displayed 012345. 20:35.450 --> 20:37.340 So this three elements will get displayed. 20:37.370 --> 20:40.310 Colon 512345 will get displayed. 20:40.310 --> 20:42.590 So it is basically coming over here till five. 20:42.620 --> 20:46.970 Then you have 6789 from five colon to till the end. 20:47.000 --> 20:48.680 Now this is very much important. 20:48.680 --> 20:49.820 Double colon two. 20:49.850 --> 20:51.200 What does this basically mean. 20:51.200 --> 20:55.250 And double colon two basically means from all the elements from first. 20:55.700 --> 20:58.580 And this two will be taken as a step size. 20:58.610 --> 20:58.880 Right. 20:58.910 --> 21:01.040 So we will jump two steps ahead. 21:01.040 --> 21:04.430 Like from here we will jump one two then three will get displayed again. 21:04.430 --> 21:07.010 Jump two steps five will be displayed from again. 21:07.010 --> 21:10.010 From this jump to two steps seven will get displayed again. 21:10.010 --> 21:10.880 Jump over here. 21:10.910 --> 21:12.380 Nine will be getting displayed. 21:12.380 --> 21:13.700 So double colon. 21:13.730 --> 21:16.160 See if I really want to make you understand about double colon. 21:16.160 --> 21:18.080 So I will go ahead and write double colon. 21:18.110 --> 21:19.970 Double colon basically means all the elements. 21:20.000 --> 21:23.750 Right now if I am writing okay fine. 21:23.780 --> 21:26.150 Uh let's give the step size as one. 21:26.150 --> 21:26.390 Then. 21:26.390 --> 21:31.450 Also I'll be getting the same output if I give the step size to two, so double jumps will be happening, 21:31.480 --> 21:31.930 right? 21:31.960 --> 21:33.490 This is basically the step size. 21:33.490 --> 21:40.120 Then if I write three then again three steps like from here one two, jump and third whichever will 21:40.150 --> 21:41.350 be the element that will get displayed. 21:41.350 --> 21:42.790 So four 710 right. 21:42.820 --> 21:44.980 So I hope you got an idea about it. 21:45.010 --> 21:46.990 Now double colon one basically means what. 21:47.020 --> 21:47.410 Okay. 21:47.410 --> 21:49.120 So double colon one. 21:49.120 --> 21:50.110 Double colon is nothing. 21:50.110 --> 21:52.330 But it is all the elements minus one okay. 21:52.360 --> 21:55.480 From previous take all the elements one by one and display it. 21:55.510 --> 21:58.300 If I go ahead and again write something like this. 21:58.300 --> 22:01.180 Let's say I go ahead and write numbers okay. 22:01.210 --> 22:03.400 Double colon minus two. 22:03.430 --> 22:06.160 Write some from back every two numbers. 22:06.160 --> 22:06.430 Right. 22:06.460 --> 22:09.670 It will skip every one number and display the other number over here. 22:09.700 --> 22:10.120 Right. 22:10.120 --> 22:12.250 So this is basically called as a slicing. 22:12.250 --> 22:15.820 And uh some of the operations will be involved in slicing. 22:15.820 --> 22:21.250 Whenever we want to retrieve some results we want to modify them, do something right so we can actually 22:21.250 --> 22:21.820 use it. 22:21.850 --> 22:22.240 Right. 22:22.270 --> 22:31.060 Now coming to the next thing is iterating over list Okay, now I've already shown you how to iterate 22:31.060 --> 22:31.900 over strings. 22:31.900 --> 22:35.110 Similarly, you can also iterate over a list, right? 22:35.110 --> 22:38.410 So for that also again I will be going and using for loop. 22:38.410 --> 22:43.420 Let's say I will go ahead and write for fruit for fruit in fruits. 22:43.450 --> 22:44.020 Right. 22:44.020 --> 22:48.820 And I will just go ahead and inside and print all the fruit items that I have. 22:49.090 --> 22:49.480 Right. 22:49.510 --> 22:53.500 So here one by one right now no fruit items is present or what. 22:53.920 --> 22:55.780 Okay, okay I have cleared that fruits. 22:55.780 --> 22:56.230 Right. 22:56.260 --> 22:57.340 So let me do one thing. 22:57.340 --> 23:02.170 Let me just take numbers over here so that I will be able to see through it. 23:02.200 --> 23:02.560 Right. 23:02.590 --> 23:05.800 For number in numbers. 23:05.800 --> 23:06.340 Right. 23:06.340 --> 23:08.530 So numbers is also a collection over here. 23:08.530 --> 23:10.150 List of collection list of elements. 23:10.150 --> 23:13.150 So 123456789 ten okay. 23:13.180 --> 23:14.320 So this is also there. 23:14.350 --> 23:18.970 Let's say I want to iterate all this list with indexes also. 23:19.450 --> 23:24.940 So I want to iterate iterating with index. 23:24.940 --> 23:31.160 So for this I can use for index, comma, fruit, fruit or index. 23:31.160 --> 23:34.460 Sorry for index comma number in numbers. 23:34.490 --> 23:37.160 Now once I use this numbers right. 23:37.190 --> 23:39.140 Obviously see if I'm directly using this number. 23:39.140 --> 23:42.260 I know this is a list but if I want index information. 23:42.260 --> 23:47.000 Also I have an inbuilt function in Python which is called as enumerate okay. 23:47.000 --> 23:52.220 And if we specifically use this enumerate that basically means we are also going to get the index number. 23:52.220 --> 23:58.010 So if I go ahead and print index comma number now you'll be able to see all the indexes. 23:58.010 --> 23:59.480 So this is my zeroth index. 23:59.480 --> 24:01.490 The first element is present in the zeroth index. 24:01.550 --> 24:06.020 Then I have two which is present in the first index then three in the second index, four in the third 24:06.020 --> 24:11.480 index, five in the fourth index, six in the fifth index, seven in the sixth index, eighth in the 24:11.480 --> 24:15.110 seventh index, nine in the eighth index, and ten in the ninth index. 24:15.110 --> 24:16.550 So I have all these things. 24:16.550 --> 24:21.830 And just by using this inbuilt function, you get an access of the index number also along with the 24:21.830 --> 24:24.380 list of elements that are present in that particular list. 24:24.410 --> 24:24.920 Okay. 24:24.920 --> 24:30.440 so this is one amazing thing about, uh, you know, you can also iterate over the list. 24:30.470 --> 24:32.540 You can also iterate along with the index. 24:32.570 --> 24:33.020 Right. 24:33.050 --> 24:39.890 Now let's go ahead and talk about one more amazing thing, which is basically called as list comprehension. 24:39.920 --> 24:40.490 Okay. 24:41.030 --> 24:43.220 Now list comprehension. 24:43.250 --> 24:47.450 Now guys let's let's consider that, uh, I want to do something right. 24:47.450 --> 24:55.940 I want to probably, uh, let's say I'll write a for loop for x in range for x in range. 24:56.000 --> 24:58.010 Let's say I'm going to write ten. 24:58.370 --> 25:04.430 And here, uh, what I'm actually going to do is that I'm going to probably create a list element. 25:04.430 --> 25:07.220 Let's say I'm going to create a list empty elements. 25:07.220 --> 25:10.460 And then I will go ahead and write list dot append. 25:10.850 --> 25:13.010 And let me just go ahead and do this. 25:13.040 --> 25:13.610 Okay. 25:13.610 --> 25:15.650 So just imagine what I've actually done. 25:16.010 --> 25:21.230 Uh, here inside this for loop I'm squaring every number and I'm appending in this particular list. 25:21.260 --> 25:21.530 Right. 25:21.530 --> 25:24.720 And finally I can go ahead and print this particular list. 25:24.750 --> 25:25.110 Okay. 25:25.140 --> 25:30.810 So in short, this is a code that I've actually written to square every numbers inside this particular 25:30.810 --> 25:31.920 range of numbers. 25:31.950 --> 25:32.280 Right. 25:32.280 --> 25:37.320 So I'm getting 01249 1625 3649, 64, 81. 25:37.350 --> 25:39.480 Now see imagine in this line of code. 25:39.510 --> 25:39.750 Right? 25:39.750 --> 25:41.790 I've written 3 to 4 lines right over here. 25:42.000 --> 25:43.890 First of all, initialized an empty list. 25:43.920 --> 25:45.510 Then I'm putting a for loop. 25:45.510 --> 25:47.760 Then I'm performing this specific operation. 25:47.760 --> 25:51.270 What if I can perform this entire list operation? 25:51.270 --> 25:55.320 Because everything is happening inside a list itself, and we are creating a new list also over here. 25:55.350 --> 25:55.950 Right? 25:55.980 --> 25:59.850 Obviously, if you're creating your list again, new list over here, again, playing with different 25:59.850 --> 26:01.890 different elements, more memory will be required. 26:01.920 --> 26:06.420 So Python actually helps us to play with list comprehension. 26:06.450 --> 26:13.980 Now in list comprehension it tells you that you can perform all this operation right within a list itself. 26:14.010 --> 26:14.460 Right. 26:14.460 --> 26:16.740 So now see this observe over here. 26:16.770 --> 26:21.840 Now I will go ahead and write for x in range. 26:23.110 --> 26:23.500 ten. 26:23.530 --> 26:23.980 Right. 26:23.980 --> 26:27.400 So here if I go ahead and execute this oh okay. 26:27.400 --> 26:30.820 Right now it is giving me an error because it is invalid syntax I get it okay. 26:30.850 --> 26:32.830 Now let's let's do this okay. 26:32.860 --> 26:35.860 So first I have written for x in range of ten. 26:35.860 --> 26:37.990 So this is basically iterating through this. 26:37.990 --> 26:40.780 Now the next thing is that what kind of operation I am performing. 26:40.780 --> 26:42.190 So I want to perform x square. 26:42.190 --> 26:45.070 So here if I go ahead and write x square. 26:45.100 --> 26:51.040 So list comprehension basically has two important things what we want as an output and what is the kind 26:51.040 --> 26:52.150 of operation that we are doing. 26:52.180 --> 26:52.480 Right. 26:52.480 --> 26:54.850 So see this is doing some kind of operation. 26:54.850 --> 26:56.230 So that needs to be displayed. 26:56.230 --> 26:57.760 And this is basically my iteration. 26:57.760 --> 26:59.170 So both of them are combined. 26:59.170 --> 27:03.460 If I go ahead and execute this you will be able to see that in a single list. 27:03.460 --> 27:05.440 I am able to get the specific answer. 27:05.440 --> 27:06.820 So here what did I do? 27:06.850 --> 27:12.160 I did not have to create other list, item or list elements as such, right? 27:12.160 --> 27:17.740 All I did is that I probably, uh, you know, executed my code within a line of code. 27:17.740 --> 27:20.290 And what I really want is x square. 27:20.320 --> 27:21.410 I have written it in forward. 27:21.440 --> 27:21.770 Right. 27:21.800 --> 27:25.550 Now let's go ahead and see more examples with respect to list comprehension. 27:25.670 --> 27:27.710 So guys we have just seen one example. 27:27.710 --> 27:30.890 And I hope I know that you may be having some kind of confusion. 27:30.890 --> 27:36.980 So it is a better way that if I really want to make you understand about list comprehension, first 27:36.980 --> 27:43.370 of all, let's talk about a specific syntax like what kind of syntax we specifically use. 27:43.400 --> 27:43.940 Okay. 27:44.030 --> 27:46.610 Now the basic syntax okay. 27:46.670 --> 27:49.820 Let me just make this as a markdown okay. 27:50.090 --> 27:51.740 Markdown over here okay. 27:51.770 --> 27:54.350 List comprehension okay. 27:54.500 --> 27:55.700 And this is important. 27:55.700 --> 27:58.820 So that is the reason I'm also going to show you the syntax over here. 27:58.850 --> 27:59.270 Okay. 27:59.300 --> 28:02.390 First of all the basic syntax. 28:02.420 --> 28:02.930 Okay. 28:03.020 --> 28:05.540 Now basic syntax is nothing. 28:05.540 --> 28:11.270 But it looks something like this expression for item in Iterables. 28:11.300 --> 28:11.630 Right. 28:11.630 --> 28:16.370 So that is what we have done for item in iterable which is traversing everything. 28:16.370 --> 28:20.030 And this expression is going to perform on all the single items. 28:20.060 --> 28:22.460 Okay, this is the basic syntax. 28:22.490 --> 28:23.030 Okay. 28:23.060 --> 28:27.380 Now I may also have other option like with conditional logic. 28:27.410 --> 28:27.710 Okay. 28:27.710 --> 28:29.780 If I want to apply some logic over here. 28:29.810 --> 28:33.650 So with conditional logic the expression looks a little bit different. 28:33.680 --> 28:34.070 Okay. 28:34.100 --> 28:37.340 And let me just show you this particular expression also okay. 28:37.370 --> 28:41.180 So here you can see expression for item in a table if condition. 28:41.180 --> 28:42.140 Also I can put. 28:42.170 --> 28:44.630 So I'm putting if condition over here. 28:44.630 --> 28:46.730 So any kind of conditional logic is there. 28:46.730 --> 28:50.270 You have to probably put it at the last iterate. 28:50.300 --> 28:54.620 Whatever iteration you really want to do, you want to put in the center and any kind of expression 28:54.620 --> 28:55.400 that you want to perform. 28:55.400 --> 28:56.870 You can put it in the starting. 28:56.900 --> 28:57.380 Okay. 28:57.410 --> 29:01.460 Now based on this we will try to see some kind of example okay. 29:01.490 --> 29:05.120 So but remember this this is super super important okay. 29:05.120 --> 29:08.240 And you have to use with respect to this itself right. 29:08.270 --> 29:11.150 So let's consider one example. 29:11.840 --> 29:15.260 So let me go ahead and write basic list comprehension. 29:18.120 --> 29:18.660 Okay. 29:18.840 --> 29:22.860 Let's say I want to do a square of all the number. 29:22.890 --> 29:23.520 Okay. 29:23.580 --> 29:25.530 Square of all the number. 29:26.520 --> 29:26.880 Okay. 29:26.910 --> 29:28.410 Square of a set of numbers. 29:28.410 --> 29:35.910 So I will write for x or for num in range of ten. 29:35.940 --> 29:36.450 Right. 29:36.480 --> 29:41.010 And for every of this number I just need to do num square. 29:42.210 --> 29:42.840 Right. 29:43.110 --> 29:43.920 Square. 29:46.230 --> 29:46.860 Done. 29:46.890 --> 29:52.440 Now if I go ahead and print this in short what I'm actually going to get, I'm going to basically get 29:52.440 --> 29:53.460 the square of this number. 29:53.490 --> 29:55.080 Now what condition I have applied over here. 29:55.110 --> 29:57.660 Basic syntax for item in iterable. 29:57.660 --> 29:59.760 And then I have expression okay. 29:59.820 --> 30:01.620 Now coming to the next one okay. 30:01.650 --> 30:06.180 Let's say let's consider with list comprehension with condition okay. 30:06.210 --> 30:08.790 A specific condition over here okay. 30:08.790 --> 30:14.730 And let's say I will try to find out from a list of elements which are which are basically even numbers. 30:14.760 --> 30:15.840 Okay, okay. 30:15.870 --> 30:17.140 Which are even numbers. 30:17.170 --> 30:22.720 Now, let's say if I go ahead and write in for loop for I in range ten. 30:22.900 --> 30:23.530 Okay. 30:24.730 --> 30:30.250 If I go ahead and write, if I colon two is double equal to zero right. 30:30.280 --> 30:32.470 Then what I have to do print. 30:32.710 --> 30:37.120 Or I will probably create a list and I'll append all the even elements right. 30:37.150 --> 30:40.750 So let's say I have created a list an empty list over here. 30:40.780 --> 30:47.650 And now what I'm actually going to do I'm going to basically write list dot append list dot append. 30:48.070 --> 30:51.400 And here I'm going to basically write my I right. 30:51.430 --> 30:58.210 So finally if I go ahead and print my list, you'll be able to see that all the even elements will come 30:58.240 --> 31:00.370 right till this particular ten number. 31:00.400 --> 31:00.910 Right. 31:01.360 --> 31:06.460 But here you need to see how do I convert this into list comprehension. 31:06.460 --> 31:10.030 And I showed you one expression with conditional logic. 31:10.060 --> 31:12.640 Expression is over here for item in iterable is here. 31:12.640 --> 31:13.960 And if condition is over here. 31:13.990 --> 31:17.270 Now the same thing I will try to convert this into a list comprehension. 31:17.270 --> 31:22.250 So I will write for I or for num in range. 31:22.760 --> 31:29.120 Range 20 okay or ten okay, I have to display the number itself so I will write number. 31:29.120 --> 31:31.430 I don't need to even apply any expression. 31:31.430 --> 31:34.130 But here I will go ahead and write one if condition. 31:34.130 --> 31:40.460 I will say hey if num percentile two or modulus two is double equal to zero. 31:40.520 --> 31:45.290 Now this basically becomes my even underscore numbers. 31:45.320 --> 31:48.950 Right now here I do not have to even create a new list. 31:48.980 --> 31:49.490 Right. 31:49.490 --> 31:51.830 All I'm doing it in one single line of code. 31:51.830 --> 31:54.890 So this way my execution will happen quicker right? 31:54.920 --> 31:55.940 It will be faster. 31:56.150 --> 31:59.210 So I hope you are getting this as an idea. 31:59.240 --> 32:01.010 Okay, now one more. 32:01.040 --> 32:02.360 One more thing, is there? 32:02.390 --> 32:02.600 Okay. 32:02.630 --> 32:07.820 One more very important, uh, thing is there, which is again a type of list comprehension you can 32:07.820 --> 32:11.150 basically say which is called as nested list comprehension. 32:11.150 --> 32:13.160 So let me just go ahead and write it down. 32:13.220 --> 32:22.310 So here you have something called as nested list comprehension okay. 32:22.310 --> 32:23.960 And it is good to know all these things. 32:23.960 --> 32:28.340 Guys I am trying my level best so that you will be able to understand multiple things. 32:28.370 --> 32:28.910 Okay. 32:29.270 --> 32:36.020 So here you can see and here you can see now what is so different when compared to this okay. 32:36.080 --> 32:40.610 Now here we are iterating through two different iterables. 32:40.610 --> 32:47.060 So for item in iterable one for item two in iterable two then we are writing an expression. 32:47.060 --> 32:49.190 So that basically means if I have two list. 32:49.190 --> 32:54.290 And then on top of that two list I want to perform any kind of list comprehension. 32:54.290 --> 32:56.570 Then I can use this nested list comprehension. 32:56.570 --> 32:59.060 So let me show you one perfect example. 32:59.090 --> 32:59.630 Okay. 32:59.660 --> 33:05.480 Let me just go ahead and write it over here and let me write it as nested list. 33:07.880 --> 33:10.490 Comprehension okay. 33:11.430 --> 33:12.870 Comprehension. 33:14.520 --> 33:17.220 So let me go ahead and create my list one. 33:17.700 --> 33:19.320 And this will be 123. 33:19.530 --> 33:20.250 Okay. 33:20.640 --> 33:34.050 Or I'll take one more element for let me say this is my list two which will be nothing but a, b, C, 33:35.610 --> 33:36.210 d. 33:36.240 --> 33:38.160 Okay, so these are my four elements. 33:38.310 --> 33:46.710 Now let me do one very simple thing okay I will try to make a pair pairs of list one and list two elements 33:46.740 --> 33:47.250 okay. 33:47.340 --> 33:51.150 So first of all I will iterate through list one. 33:51.150 --> 33:54.540 So let me just go ahead and write for I in list one. 33:54.570 --> 33:55.140 Okay. 33:55.230 --> 33:59.610 Then I will iterate through list two for j in list two okay. 33:59.610 --> 34:01.980 And then I have to pair it. 34:01.980 --> 34:07.200 Right now for pairing I will be using a tuple I have not discussed yet about a tuple, but I'm just 34:07.200 --> 34:09.810 going to take this I and j and pair it together. 34:09.840 --> 34:11.410 Okay, just write it in this way. 34:11.440 --> 34:13.690 Okay, now you can see. 34:13.690 --> 34:17.440 Or if you don't want to, like, write like this, you can also use list over here. 34:17.740 --> 34:18.040 Okay. 34:18.070 --> 34:19.960 Let's see whether this will work or not. 34:19.960 --> 34:22.510 And now I'm just going to print pair. 34:24.340 --> 34:25.030 Okay. 34:25.180 --> 34:25.810 Appear. 34:25.840 --> 34:27.490 Appear have written pair. 34:27.790 --> 34:33.460 Okay so here you can see one comma one comma b one comma c one comma two comma two comma b two comma 34:33.490 --> 34:34.360 c two comma d. 34:34.450 --> 34:40.120 So it is just doing all the pairing 1A1B1C1D2A2B2C2D. 34:40.120 --> 34:41.620 So this is what is happening. 34:41.650 --> 34:44.770 First of all this will iterate right with respect to one element. 34:44.770 --> 34:46.930 Then it will iterate all the elements right. 34:46.960 --> 34:49.810 We can also write this in this particular way also. 34:49.840 --> 34:50.080 Right. 34:50.110 --> 34:53.080 But again a lot of lines of code we really need to write. 34:53.080 --> 34:55.060 But this is really really powerful. 34:55.060 --> 34:59.650 And here you can actually see with the help of nested list comprehension we are able to do it right 34:59.740 --> 35:01.450 now in Python. 35:01.450 --> 35:04.630 Also you have lot of inbuilt functions right. 35:04.630 --> 35:13.190 So we can actually use list comprehension List comprehension with function calls. 35:13.400 --> 35:20.210 You can create your own custom function and all, but right now I'm going to show you some, uh, inbuilt 35:20.210 --> 35:20.720 functions. 35:20.750 --> 35:21.290 Okay. 35:21.290 --> 35:23.240 So inbuilt function will try to see. 35:23.240 --> 35:28.340 So list comprehension with this let's say and I will I'll show you the code over here. 35:28.340 --> 35:32.690 So here I have words like hello world Python list comprehension. 35:32.720 --> 35:34.400 Now see everybody focus. 35:34.400 --> 35:37.310 So I'm writing for words in words and I'm just saying length of word. 35:37.340 --> 35:37.730 Right. 35:37.730 --> 35:40.580 So it is just going to give us the length of word over here. 35:40.610 --> 35:41.030 Right. 35:41.030 --> 35:44.330 And how easily we are able to see this particular output. 35:44.360 --> 35:44.960 Right. 35:44.960 --> 35:46.970 And this looks amazing. 35:46.970 --> 35:47.270 Right. 35:47.270 --> 35:51.890 And most of the things are basically very much simple over here right now. 35:51.890 --> 35:58.970 Uh, there is also one more list comprehension technique where you can use else block also. 35:58.970 --> 36:01.610 So, uh, I will give you that as an assignment. 36:01.610 --> 36:02.900 Please make sure that you do it. 36:02.900 --> 36:07.340 But don't worry as we go ahead and run, learn more about the tuples and all there. 36:07.340 --> 36:12.740 Also, we'll be covering more about it, but I hope you got an idea with respect to list comprehension. 36:12.740 --> 36:19.880 And this was all about the discussion with respect to list, and I think I tried my level best to cover 36:19.880 --> 36:21.740 almost each and every thing. 36:21.830 --> 36:22.220 Okay. 36:22.250 --> 36:26.300 And at the end of the day, you really need to try more and more to understand more. 36:26.330 --> 36:28.310 Example, unless you don't practice. 36:28.310 --> 36:29.660 Uh, I don't think so. 36:29.660 --> 36:33.050 You will be able to do any perfection in this. 36:33.050 --> 36:33.380 Right. 36:33.380 --> 36:35.150 So more examples, more things. 36:35.150 --> 36:39.620 But at the end of the day, I would like to give the conclusion of this lesson and probably talk about 36:39.620 --> 36:42.320 it, you know, because list is something really important. 36:42.320 --> 36:43.340 So the list. 36:44.060 --> 36:48.620 So here you can see I have given some conclusion with respect to the list comprehension are powerful 36:48.620 --> 36:49.130 and concise. 36:49.130 --> 36:55.610 To create list in Python they are syntactically syntactically compact and can replace more verbose looping 36:55.610 --> 36:56.180 construct. 36:56.210 --> 37:00.980 Understand the syntax of list comprehension will help you write cleaner and more efficient Python code, 37:01.010 --> 37:01.550 right? 37:01.610 --> 37:03.470 So yes, this was it. 37:03.470 --> 37:07.220 Uh, I will see you all in the next video where we will be talking about the next data structure. 37:07.250 --> 37:07.430 Thank.