1
00:00:00,260 --> 00:00:06,350
Lists work well for storing collections of items that can change through the list of a program.

2
00:00:06,350 --> 00:00:12,380
So the ability to modify lists is particularly important when you are working with a list of users on

3
00:00:12,380 --> 00:00:14,870
a website or a list of characters in a game.

4
00:00:14,900 --> 00:00:20,300
So, however, sometimes you will want to create a list of items that cannot change.

5
00:00:20,300 --> 00:00:24,770
So tuples allows you to do just that.

6
00:00:25,160 --> 00:00:31,760
So Python refers to values that cannot change as immutable and immutable.

7
00:00:31,760 --> 00:00:33,650
List is called tuple.

8
00:00:33,680 --> 00:00:39,640
So a tuple is just like a list, except you use parentheses instead of a square braces.

9
00:00:39,650 --> 00:00:45,680
Once you define a tuple, you can access individual elements by using each item's index, just as you

10
00:00:45,680 --> 00:00:46,940
would for a list.

11
00:00:46,970 --> 00:00:48,670
For example, if we have a.

12
00:00:51,520 --> 00:00:52,360
Rectangle.

13
00:00:52,360 --> 00:00:54,580
That should always be a certain size.

14
00:00:54,580 --> 00:00:56,470
We can ensure that it is.

15
00:00:56,770 --> 00:01:00,700
Its size doesn't change by plotting the dimensions into a tuple.

16
00:01:00,790 --> 00:01:08,020
So my dimensions here, we will add 250 here and 100 here.

17
00:01:08,020 --> 00:01:13,450
And here we will print first, we will print dimension one and then we will print.

18
00:01:13,810 --> 00:01:14,130
Oops.

19
00:01:14,380 --> 00:01:15,340
Not like that.

20
00:01:15,790 --> 00:01:17,650
Of course we need to get the variable name.

21
00:01:17,650 --> 00:01:22,210
So my dimensions one here and here.

22
00:01:22,210 --> 00:01:27,790
As you can see here, we define the tuple dimensions using the parentheses instead of a square braces

23
00:01:27,790 --> 00:01:29,920
like we did in lists.

24
00:01:29,920 --> 00:01:35,650
So then we print each element in the tuple individually using the same syntax we have been using to

25
00:01:35,650 --> 00:01:37,180
access elements in a list.

26
00:01:37,180 --> 00:01:42,700
And as you can see here, we first printed to 250 and 200 after that.

27
00:01:42,700 --> 00:01:49,900
So this so and actually, let's see what happens if we try to change the item or change one of the items

28
00:01:49,900 --> 00:01:53,690
in the in the type in the tuple dimensions.

29
00:01:53,720 --> 00:01:58,400
Now here we will write my dimension actually, let's make name it my tuple, right?

30
00:01:58,400 --> 00:02:02,810
So it will more explanatory my tuple dimensions.

31
00:02:02,810 --> 00:02:07,820
And here we will use the my table dimensions equals zero.

32
00:02:07,850 --> 00:02:08,450
Make it.

33
00:02:08,450 --> 00:02:11,240
Let's make zero two.

34
00:02:12,460 --> 00:02:14,050
150 here.

35
00:02:14,080 --> 00:02:19,510
And after that, print this multiple dimensions zero.

36
00:02:20,770 --> 00:02:24,070
And after that my print, my tuple dimensions one.

37
00:02:25,320 --> 00:02:26,340
And here.

38
00:02:26,990 --> 00:02:29,270
So this is the error we got here, actually.

39
00:02:29,390 --> 00:02:30,530
Delete this for now.

40
00:02:30,530 --> 00:02:38,210
So this code tries to change the value of the first dimension, but Python returns a type error because

41
00:02:38,210 --> 00:02:43,220
we're trying to alter a tuple which can't be done to that type of object.

42
00:02:43,220 --> 00:02:49,520
And Python tells us we can't assign a new value to an item in a tuple here.

43
00:02:49,520 --> 00:02:53,420
As you can see here, Tuple object does not support item assignment.

44
00:02:53,420 --> 00:02:58,580
So this is a beneficial because we want to python raise an error when a line of code tries to change

45
00:02:58,580 --> 00:03:05,600
the dimensions of the rectangle and tuples are technically defined by the presence of a comma, so the

46
00:03:05,600 --> 00:03:08,540
parentheses make them look neater and more readable.

47
00:03:08,540 --> 00:03:15,350
So if you want to define a tuple with one element, you need to include trailing comma here.

48
00:03:15,500 --> 00:03:21,320
So if you want to define tuple, just one element, you need to include this trailing comma.

49
00:03:21,770 --> 00:03:25,400
So it doesn't often make sense to build a tuple with one element.

50
00:03:25,400 --> 00:03:29,880
But this can happen when tuples are generated automatically.

51
00:03:29,880 --> 00:03:37,050
So you can also loop through all values in a tuple, so you can loop over all the values in a tuple

52
00:03:37,050 --> 00:03:41,370
using just the for loop as we did in previous lectures with lists.

53
00:03:41,370 --> 00:03:46,740
So here now we will add new tuple.

54
00:03:46,740 --> 00:03:51,270
So my tuple or my car models.

55
00:03:51,300 --> 00:03:52,230
Models.

56
00:03:53,360 --> 00:04:01,160
My favorite, favorite car models that I will like forever.

57
00:04:01,160 --> 00:04:05,850
And this is not the best name for that, but I just explanatory purposes.

58
00:04:05,870 --> 00:04:10,400
And here we will add tuples that for example, I like BMW cars.

59
00:04:10,820 --> 00:04:13,520
I like the here.

60
00:04:13,520 --> 00:04:19,610
For example, I like Volkswagen, but the sporty sporty ones here, I like sports here.

61
00:04:19,610 --> 00:04:20,870
So that's it for.

62
00:04:21,990 --> 00:04:24,960
And here we will loop through all the topics in this lesson.

63
00:04:24,990 --> 00:04:28,110
So for so remember, this is not a list.

64
00:04:28,760 --> 00:04:31,170
This is actually let me here.

65
00:04:31,280 --> 00:04:34,340
So remember, keep in mind that this is not a list.

66
00:04:34,340 --> 00:04:36,350
This is tuple.

67
00:04:37,480 --> 00:04:38,890
This is tuple here.

68
00:04:39,070 --> 00:04:42,040
So here we will loop through all the items in this list.

69
00:04:42,130 --> 00:04:47,650
So for my my fave car.

70
00:04:49,680 --> 00:04:50,820
And here.

71
00:04:53,710 --> 00:04:54,310
We will do.

72
00:04:55,660 --> 00:05:00,580
In my favorite car models that I will like forever.

73
00:05:00,580 --> 00:05:04,810
And here we will print here my my fave car.

74
00:05:04,810 --> 00:05:06,370
And let's print this.

75
00:05:08,000 --> 00:05:10,760
And here, as you can see here, we loop through all the elements here.

76
00:05:10,760 --> 00:05:15,690
So Python returns all the elements in a tuple, just as it would for a list.

77
00:05:15,710 --> 00:05:18,350
So although you can modify a tuple.

78
00:05:18,350 --> 00:05:20,900
So that's it how it how this works here.

79
00:05:20,900 --> 00:05:28,070
So although you can't modify a tuple, you can assign a new value to a variable that represents a tuple.

80
00:05:28,070 --> 00:05:35,390
For example, if you wanted to change the dimensions of a previously created rectangle dimensions here,

81
00:05:35,390 --> 00:05:36,110
for example.

82
00:05:36,140 --> 00:05:37,250
250.

83
00:05:38,690 --> 00:05:40,340
150 and 100.

84
00:05:41,450 --> 00:05:45,230
And we will print the original dimensions here.

85
00:05:46,300 --> 00:05:48,310
Original dimensions.

86
00:05:48,340 --> 00:05:49,630
Dimensions here.

87
00:05:49,630 --> 00:05:53,890
And after that we will create a for loop dimension.

88
00:05:54,580 --> 00:05:57,430
Dimension in dimensions.

89
00:05:57,430 --> 00:06:01,900
And after that we will print.

90
00:06:02,740 --> 00:06:05,740
Here, we will print the dimension.

91
00:06:07,050 --> 00:06:08,190
Parental dimension.

92
00:06:09,360 --> 00:06:10,110
Dimension.

93
00:06:10,260 --> 00:06:12,870
And here we will.

94
00:06:12,930 --> 00:06:15,960
After that we will do again dimensions.

95
00:06:15,960 --> 00:06:17,460
We will change the dimensions here.

96
00:06:17,490 --> 00:06:19,260
Dimensions.

97
00:06:20,420 --> 00:06:24,500
And equals, for example, 502 hundred.

98
00:06:24,500 --> 00:06:25,010
Right.

99
00:06:25,220 --> 00:06:34,580
And after that, we will print this new line, modified dimensions, modified dimensions.

100
00:06:35,000 --> 00:06:37,700
And here we will create a new for loop.

101
00:06:37,700 --> 00:06:39,920
Actually, let's use double dot here.

102
00:06:40,700 --> 00:06:41,900
Make it look nicer.

103
00:06:42,030 --> 00:06:42,560
Right.

104
00:06:42,560 --> 00:06:44,820
So for dimension.

105
00:06:45,370 --> 00:06:46,430
Dimension.

106
00:06:47,510 --> 00:06:50,300
Dimension in dimensions.

107
00:06:50,300 --> 00:06:54,260
And here we will print dimension again.

108
00:06:54,290 --> 00:06:55,250
That's it.

109
00:06:55,490 --> 00:06:56,930
And here we will.

110
00:06:56,930 --> 00:06:58,670
Let's run it.

111
00:07:02,160 --> 00:07:04,530
And here this is our output.

112
00:07:04,530 --> 00:07:12,810
So the first four lines define the original tuple and the initial dimensions, and we then associate

113
00:07:12,810 --> 00:07:18,090
a new tuple with the variable dimensions and print the new value.

114
00:07:18,090 --> 00:07:24,390
And Python doesn't raise any error this time because resigning a variable is valid.

115
00:07:24,540 --> 00:07:31,980
So when compared with list tuples are simple data structures and use them when you want to store a set

116
00:07:31,980 --> 00:07:36,630
of values that should not be changed throughout the life of a program.