1
00:00:00,605 --> 00:00:05,460
'Kay, so here we are back in quiz.py and
let's go ahead and finish this out.

2
00:00:05,460 --> 00:00:08,980
I think I'm actually going to start down
here in the summary.

3
00:00:08,980 --> 00:00:12,980
I think that will be faster and easier to
build first.

4
00:00:12,980 --> 00:00:16,230
So let's handle this first one, this print
how many you got right.

5
00:00:16,230 --> 00:00:19,689
So let's say, print and

6
00:00:19,689 --> 00:00:25,630
You got something out of something right.

7
00:00:26,630 --> 00:00:28,490
And then we'll do a format.

8
00:00:28,490 --> 00:00:35,209
And we'll put in here self.total_correct
and len(self.questions).

9
00:00:36,940 --> 00:00:38,300
And then we'll close that.

10
00:00:38,300 --> 00:00:42,310
So, what's with this self.total_correct?

11
00:00:42,310 --> 00:00:44,170
We're gonna have to remember to make a new
function.

12
00:00:44,170 --> 00:00:45,816
So let's just make a note up here about
that.

13
00:00:45,816 --> 00:00:48,382
Def total_correct.

14
00:00:48,382 --> 00:00:50,340
Sorry, I keep saying function.

15
00:00:50,340 --> 00:00:52,320
We're gonna begin new method.

16
00:00:52,320 --> 00:00:57,250
Return the total number of correct
answers.

17
00:00:57,250 --> 00:00:58,510
Okay.

18
00:00:58,510 --> 00:01:01,940
So, there's that, and we, I said you got
blank out of blank.

19
00:01:01,940 --> 00:01:05,640
We could do this as like five out of ten,
right?

20
00:01:05,640 --> 00:01:08,270
I just like the, being a bit more verbose
there.

21
00:01:08,270 --> 00:01:11,226
Okay, and then we wanna print how long it
took.

22
00:01:11,226 --> 00:01:18,618
So, let's say It took you blank seconds
total.

23
00:01:18,618 --> 00:01:22,116
And then we're gonna call .format.

24
00:01:22,116 --> 00:01:30,062
And we're gonna put in self.end_time minus
self.start_time .seconds.

25
00:01:30,062 --> 00:01:33,410
And then we're gonna close that off.

26
00:01:33,410 --> 00:01:36,850
Okay, so now why do I have parentheses
around this?

27
00:01:36,850 --> 00:01:38,920
This isn't like a function or anything.

28
00:01:38,920 --> 00:01:43,672
So, the reason is because I want Python to
calculate what's in self.end_time

29
00:01:43,672 --> 00:01:45,130
minus self.start_time.

30
00:01:45,130 --> 00:01:48,550
I want to, to calculate that and give me
back this like temporary

31
00:01:48,550 --> 00:01:52,500
unnamed invisible variable, which is the
time delta, right?

32
00:01:52,500 --> 00:01:56,080
Because when we subtract one date time
from another, we get a time delta.

33
00:01:56,080 --> 00:01:58,590
And then I wanna get the seconds off of
that.

34
00:01:58,590 --> 00:02:02,440
So this is gonna be, you know, 50, or
whatever.

35
00:02:02,440 --> 00:02:03,060
Okay.

36
00:02:03,060 --> 00:02:04,860
We have to write this total correct.

37
00:02:04,860 --> 00:02:05,770
How do we write total correct?

38
00:02:05,770 --> 00:02:06,480
How do we figure this out?

39
00:02:06,480 --> 00:02:09,230
Well, there's a couple different ways to
do this.

40
00:02:09,230 --> 00:02:12,040
I would actually do this in a very
different way if

41
00:02:12,040 --> 00:02:14,420
I was doing this just on my own.

42
00:02:14,420 --> 00:02:18,040
But as far as like, teaching this, and
with what I've taught you so far,

43
00:02:18,040 --> 00:02:21,270
cuz I haven't taught you like functional
programming, I so wanna do it.

44
00:02:21,270 --> 00:02:22,850
Anyway though, since I haven't done that,

45
00:02:22,850 --> 00:02:24,920
we've gotta do this in a slightly slower
way.

46
00:02:24,920 --> 00:02:25,870
So, here's what we're gonna do.

47
00:02:25,870 --> 00:02:28,010
We're gonna do total equals 0.

48
00:02:28,010 --> 00:02:34,630
And for answer in self.answers, all right?

49
00:02:34,630 --> 00:02:39,375
If answer[0], then total plus equals 1.

50
00:02:41,690 --> 00:02:44,150
Return total, 'kay?

51
00:02:44,150 --> 00:02:45,050
So, what are we doing here?

52
00:02:45,050 --> 00:02:46,810
Well, so we're kinda doing two things.

53
00:02:46,810 --> 00:02:51,550
First of all, we are saying that each
answer that's in self.answers is

54
00:02:51,550 --> 00:02:55,690
going to have, it, it's going to be a list
or tuple whatever itself.

55
00:02:55,690 --> 00:02:58,590
And we're saying that the first item is
going to be

56
00:02:58,590 --> 00:03:01,940
either whether they got the question right
or whether they got the question wrong.

57
00:03:01,940 --> 00:03:04,810
So, all I'm gonna put in here is I'm gonna
put in True or False.

58
00:03:04,810 --> 00:03:08,730
So, what we're effectively saying here on
35 is the exact same thing

59
00:03:08,730 --> 00:03:10,962
as us doing that, if answer[0] equal to
True.

60
00:03:10,962 --> 00:03:17,090
But answer[0] will either be the literal
Boolean True or the literal Boolean False.

61
00:03:17,090 --> 00:03:20,130
So, we don't have to have the equals True.

62
00:03:20,130 --> 00:03:22,630
We can just say if answer[0].

63
00:03:22,630 --> 00:03:23,680
So it's anything truthy.

64
00:03:23,680 --> 00:03:26,460
This is why we would, we would them, we
would not wanna put in, say,

65
00:03:26,460 --> 00:03:27,689
just an empty string, okay?

66
00:03:27,689 --> 00:03:29,224
Well, actually that would come back False,
so that'd be okay.

67
00:03:29,224 --> 00:03:30,280
We, we wanna be careful.

68
00:03:30,280 --> 00:03:33,130
We wanna be sure to actually put in Trues
and Falses.

69
00:03:33,130 --> 00:03:33,780
That's fine.

70
00:03:33,780 --> 00:03:34,710
That's cool.

71
00:03:34,710 --> 00:03:39,160
So, all we're missing now is everything
else.

72
00:03:39,160 --> 00:03:40,020
Where do we start?

73
00:03:40,020 --> 00:03:43,239
Let's actually go back here to the init
cuz I think the init's gonna be, and

74
00:03:43,239 --> 00:03:45,480
[UNKNOWN] to generate ten questions,
right?

75
00:03:45,480 --> 00:03:46,275
That's not that bad.

76
00:03:46,275 --> 00:03:47,070
Okay.

77
00:03:47,070 --> 00:03:51,500
So, let's hold on to what our
question_types are.

78
00:03:51,500 --> 00:03:53,280
So, questions_types, we're gonna have two
of these.

79
00:03:53,280 --> 00:03:55,050
We're gonna have Add and we're gonna have
Multiply.

80
00:03:56,090 --> 00:04:00,980
Now, these are the class names that we
imported, right?

81
00:04:00,980 --> 00:04:03,130
Exact same names there.

82
00:04:03,130 --> 00:04:04,508
So these actually represent the classes.

83
00:04:04,508 --> 00:04:09,355
So I could now do question_types[0], 1,
and 1,

84
00:04:09,355 --> 00:04:13,180
and I would get an Add question of 1 plus
1.

85
00:04:13,180 --> 00:04:16,700
You know, or 1 plus 5, or whatever.

86
00:04:16,700 --> 00:04:19,320
So, this is now the class.

87
00:04:19,320 --> 00:04:22,630
And this is when we call the class and
pass it arguments.

88
00:04:22,630 --> 00:04:24,210
It's a little bit weird.

89
00:04:24,210 --> 00:04:26,770
But it's something you're gonna see more
and more often, and

90
00:04:26,770 --> 00:04:31,520
it's a way that we don't have to have
these like throw away extra variables.

91
00:04:31,520 --> 00:04:34,160
Okay, so we've got our question_types.

92
00:04:34,160 --> 00:04:38,490
Now we need to generate ten random
questions.

93
00:04:38,490 --> 00:04:39,990
So, we need a for loop.

94
00:04:39,990 --> 00:04:41,390
I wanna do this ten times.

95
00:04:41,390 --> 00:04:44,420
So for _ in range(10).

96
00:04:44,420 --> 00:04:47,090
Oh, what's with using the underscore?

97
00:04:47,090 --> 00:04:48,100
Why an underscore?

98
00:04:48,100 --> 00:04:50,610
Well, underscore tells Python

99
00:04:50,610 --> 00:04:53,470
that we don't really care what the value
is that comes out.

100
00:04:53,470 --> 00:04:57,070
I don't care that it's 0, 1, 2, 5, 8,
whatever.

101
00:04:57,070 --> 00:05:00,190
I just want it to count this number of
times, right?

102
00:05:00,190 --> 00:05:01,860
So, we're basically just saying, throw
away the value.

103
00:05:01,860 --> 00:05:02,480
I don't care.

104
00:05:02,480 --> 00:05:05,630
Just make sure the loop goes this number
of times.

105
00:05:05,630 --> 00:05:07,630
So, I'm gonna do this ten times.

106
00:05:07,630 --> 00:05:10,448
Now, this is a place where you might wanna
make the app a bit more extensible.

107
00:05:10,448 --> 00:05:15,400
Maybe when you've instantiate the quiz,
you want to say, I want 20 questions, or

108
00:05:15,400 --> 00:05:17,950
100 questions, or two questions, right?

109
00:05:17,950 --> 00:05:21,250
Now we want to do something ten times.

110
00:05:21,250 --> 00:05:25,250
And the thing we wanna do is we want to
take self.questions and

111
00:05:25,250 --> 00:05:27,790
we want to append something to it.

112
00:05:27,790 --> 00:05:29,080
What do we want to append?

113
00:05:29,080 --> 00:05:30,530
Well, let's do this.

114
00:05:30,530 --> 00:05:34,350
We can do question equals question_types.

115
00:05:34,350 --> 00:05:40,009
Actually here, let's say num1 is
random.randint between 1 and 10.

116
00:05:41,050 --> 00:05:45,820
And num2 equals random.randint between 1
and 10, 'kay?

117
00:05:45,820 --> 00:05:51,020
Now, this is another place where we might
want to make this extensible,

118
00:05:51,020 --> 00:05:54,330
to where they can say, oh, I want numbers
from 5 to 50.

119
00:05:54,330 --> 00:05:58,240
Now, I have two random numbers, and

120
00:05:58,240 --> 00:06:03,161
I wanna do a random.choice here cuz I want
it to

121
00:06:03,161 --> 00:06:07,480
grab me a random question type, right?

122
00:06:07,480 --> 00:06:09,360
I want to be either add or multiply.

123
00:06:09,360 --> 00:06:10,000
Okay.

124
00:06:10,000 --> 00:06:13,170
But when I build one of these classes, I
have to give it numbers, so

125
00:06:13,170 --> 00:06:16,750
it gave me back my random number or my
random class.

126
00:06:16,750 --> 00:06:19,930
Now we put in num1 and num2, 'kay?

127
00:06:19,930 --> 00:06:22,520
And then this appends question.

128
00:06:22,520 --> 00:06:23,084
So that's what this comment.

129
00:06:23,084 --> 00:06:25,837
[BLANK_AUDIO]

130
00:06:25,837 --> 00:06:26,466
Is right here.

131
00:06:26,466 --> 00:06:30,650
Add these questions in the self.questions,
'kay?

132
00:06:30,650 --> 00:06:32,500
So, this is kinda crazy looking.

133
00:06:32,500 --> 00:06:35,717
It's kinda weird, right, calling this
random.choice thing,

134
00:06:35,717 --> 00:06:36,990
and then putting this in?

135
00:06:36,990 --> 00:06:41,570
It's weird, but it's something you're
gonna start to see more and more often.

136
00:06:41,570 --> 00:06:44,780
This is fairly common, having a, a class
that just kind of,

137
00:06:44,780 --> 00:06:47,590
is in this ephemeral state, and then we're
gonna use it.

138
00:06:47,590 --> 00:06:50,000
We don't actually care about holding onto
that class at the time.

139
00:06:51,280 --> 00:06:54,770
Okay, so we're gonna go through it, and we
put pass into each of these functions so

140
00:06:54,770 --> 00:06:56,628
that they just sit there.

141
00:06:56,628 --> 00:06:59,334
All right, and now let's test this out.

142
00:06:59,334 --> 00:07:06,515
We're gonna come down here, and we're
gonna do python and from quiz import Quiz.

143
00:07:06,515 --> 00:07:07,920
'Kay, so we've got a quiz.

144
00:07:07,920 --> 00:07:12,792
So, let's say quiz1 equals Quiz().

145
00:07:12,792 --> 00:07:16,120
And I should be able to do quiz1.answers
and get back nothing.

146
00:07:16,120 --> 00:07:18,275
And I should be able do quiz1s.,.

147
00:07:18,275 --> 00:07:19,800
quiz1.questions.

148
00:07:19,800 --> 00:07:23,460
And look at that, I got a whole bunch of
questions.

149
00:07:23,460 --> 00:07:31,040
So, I should be able to look at, say, the
first one and see what the text is.

150
00:07:31,040 --> 00:07:31,885
So, 10 times 5.

151
00:07:31,885 --> 00:07:32,630
Okay.

152
00:07:32,630 --> 00:07:34,680
So, when I look at answer here, it should
be 50.

153
00:07:34,680 --> 00:07:35,530
And it is.

154
00:07:35,530 --> 00:07:36,384
Awesome.

155
00:07:36,384 --> 00:07:38,569
[BLANK_AUDIO]