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This is the solution of the exercises
for the level 2 of this course.

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So the first exercise is
actually here. You have

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to ask for the name and
age of a user and print

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the info. So basically
that's the function.

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So I'm not going to
rewrite it one more time.

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What I advised you to
do was to actually try to

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rewrite it by yourself
and see if you can get

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this also. Okay. Now
I'm going to go to the

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second exercise which
is to ask the user for

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two integer numbers,
add them, print the result.

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So I'm going to create
a new Python file here

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and let's say add to
it. I'm going to name it

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add to it. So I'm going
to create a function

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which is going to add
two numbers. So add

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two numbers. Okay. You
can use numbers inside

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function names. Just
make sure you don't start

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with a number. And well,
for each word you add

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an underscore. And then
I will need two parameters

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here. I will need number
one and number two.

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So I can use A and B
here. So I told you to

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use meaningful names
and maybe avoid A and B.

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But if you just need to
add two numbers, using

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A and B actually makes
much more sense. Then I'm

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just going to do return
A plus B. Okay. This is

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very easy to read. So
this function is quite easy.

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We just receive two
parameters. We return the same

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of those parameters.
Now I'm going to go back to

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the normal invitation
and I'm going to do input.

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Enter number one. Okay.
And then input. Enter

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number two. In order
to keep this and be able

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to do something with
that, I'm going to save it.

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So number one is equal
to input. And then number

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two is equal to input.
Okay. I'm going to save

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those into variables.
And because the input

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is returning a string,
I need to cast it with

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int like this. Okay. Int
number one. Int number

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two. I have my number
one, my number two.

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Now what I can do, I
can do print. So I'm going

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to do all that in one
line. And let's say str

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number one. So now that I have casted
number one, so the input into the integer,

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if I want to print it, I
need to cast it again to a

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string. Okay. So number
one plus and then the plus

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sign plus str number
two plus and then equal,

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then plus. And I can
call the function add two

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numbers. I can use the
autocompletion. And I'm

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going to give number one
and number two. As you

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can see, the line starts
to be quite long. So

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what I can do, I can
after here, after this,

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I can come back to a
new line. And this is going

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to work. So make sure
you have the correct amount

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of parentheses. And if
you have an instruction

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that is quite long, well,
you can cut this. Okay.

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So if you have a plus,
for example, you can cut

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at the plus, just go back
to a new line with some

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indentation. Okay. It's
going to automatically

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indent this. Actually, the
number of indentations

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here is not important.
Okay. Or if you have a

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comma, this is also a
good place to cut the line.

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If you have a comma, you can just go back
to a new line. It's going to work also.

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So now I'm going to
run that, actually add two

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ints. So I need to run
the dot add two ints.

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And turn number one, two,
and turn number two, five.

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And we have an error
because I also need to cast

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the results as a string.
Okay. The result is an

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integer. I need to cast
the result as a string.

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I run add two ints. So
enter number one, three,

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number two, four. And
we can see three plus four

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is equal to seven. So
that's the program. Okay.

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Now let's go to the number
three. We have to create

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a list of float numbers,
compute the average,

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and print the average.
So again, new Python file.

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Let's say compute
average from list. And I'm

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going to create def
compute. So let's name it

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compute list average.
Okay. And number list.

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Okay. So one function
which is named compute list

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average with one
parameter, which is the list.

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And I can do return sum
number list divided by

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length of number list.
Okay. I compute the sum.

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I divide by the length.
And this is a function.

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So now I can use this
for any list I have. So

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number list is equal
to, let's say, three, four,

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five, two. Okay. So I'm
going to use integers here.

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You could use float
numbers, but it's going to

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work also with integers.
And then I can do print.

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Let's just print the
results here. Compute list

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average from number list.
And I can run the program,

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run compute average
from list. And you can see

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three point five. So
one thing to note here is

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that I use number list
here and number list here.

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But as you can see, this
is a different scope. This

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is a global variable I
use here. This is a local

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variable I use inside the
function. Note also that

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I didn't cast the result,
which is here a float

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number. Okay. I didn't
cast the result as a string,

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but it's still working
with the print function.

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Why is that? Because
if you just pass one

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parameter, okay, if you
don't concatenate with

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other strings, you can
just pass an integer or

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float and it's going to
work. Okay. And now the

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exercise number
four, I'm going to create

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another Python file named
Celsius to Fahrenheit.

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And I'm going to create
def Celsius to Fahrenheit.

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Okay. And the
parameter will be actually.

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Celsius degrees. Okay.
So this is a quite common

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name to give when you
have a function that converts

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something into something
else. You can start with

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what you want to convert
and then you add two,

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the two keywords, and
then the result you want

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to get. So Celsius to
Fahrenheit or kilometers to

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meters, miles, two inches,
whatever. Okay. And

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of course I need to pass
the degrees I want to

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convert. So the Celsius
degrees. And we are going

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to apply the formula.
Okay. And I can just do also

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here return Celsius
degrees multiplied by 1.8

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plus 32. And this is going
to give the Fahrenheit

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degrees. So now in the
main, I can do print, let's

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say 20 degrees Celsius
is equal to, and then plus

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str, I'm going to make
sure that I cast the

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result as a string, Celsius
to Fahrenheit of 20.

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And I'm going to add
another plus to put degrees

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Fahrenheit. Okay. Let's
see how it works. So run

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Celsius to Fahrenheit.
We have a problem here.

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Because as you can
see here, I opened the

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parentheses here for
string. I need to close it

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here. And we have one
parentheses that is not

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correctly placed here.
So make sure, as you can

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see, that is a common
source of errors. Okay.

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Make sure that the
parentheses are in the right

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order. And you can see
here, it's quite easy to

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see with PyCharm. Okay.
So I run this. And you can

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see that when it is actually
68 Fahrenheit degrees,

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it is 20 degrees Celsius.
Okay. If you want, you

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can just copy this
multiple times. And let's say

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you want to check 25. Here, 25. You can do
this. Okay. 25 degrees. You get 75 degrees.

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All right. And that is the end
of the level two of this course.