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[No audio]

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As you know from the previous lectures, we have

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defined this function and here we are calling it.

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So it checks if the given temperature is greater

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than 7 and it returns warm if that is

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true, and cold if the temperature is equal to

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7 or lesser than 7, that's fine.

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But what is the use of this

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function in a real life setting?

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Like, who is giving this input?

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You as a programmer, you are writing this function for

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someone else so that they can use it, but you

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don't expect them to edit the Python file,

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like to have an editor like

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Visual Studio Code or other editors.

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And then you cannot just tell them to go to

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line 7 and change the value and then execute that

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code to get different outputs depending on the value.

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So how about prompting the user to enter a value

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and then the user types in the value, and then

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we get that value and process it in our function.

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In that case, we get that value and

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put it in here in the function call.

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Let's do that.

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So we've got a function there.

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We want to get a value from the user.

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To get a value from the

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user, you use the input function.

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The input function gets an argument and that is the message

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you want to show to the user on the command line.

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For example, Enter temperature.

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[Author typing]

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Maybe put a colon there if you like.

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You can write whatever you like.

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Let me save this script and execute it.

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You see now I execute it,

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and this input function, what it does is

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it freezes the execution of a program and

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waits for user input on the command line.

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So if I put input something here, like seven,

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in this case, what's going to happen is that

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this expression here will be equal to seven.

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However, because we didn't do anything here, nothing

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will happen if we print out this value,

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[Author typing]

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for example, seven, you'll get printed out

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the value of this, which is 7.

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So there you can put anything you want, Hi

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there, and you get Hi there, printed out.

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What I would suggest is, instead of printing this

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out, you'd first want to put it in a

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variable that would make it more readable.

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So user_input,

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and then you can do whatever you

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want with that variable, like lower it.

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So to print out the lowercase version of that Hi Hi.

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So you get hi hi with lowercase letters.

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Okay, back to our function.

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Let me now try to print out the weather_condition

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function output with a value of, well, user_input,

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whatever the user enters as input.

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So I'll execute the program

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now, the program will ask me with Enter temperature.

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The program will ask me to enter a temperature.

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So the execution is frozen at this point.

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This line has not been executed yet.

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It will be executed after we give

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a value here and press Enter.

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So let me write down 6.

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Let's see what we're going to get.

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This time we get an error.

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Let's read the error carefully.

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It's about file basics.py, which is our file.

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Okay, the error happened at first at this line here.

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So here print(weather_condition(user_input)).

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When Python tried to execute this

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line, it couldn't do it.

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And why?

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Well, you have to follow the error.

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So steel line basics.py, line 2 at this line.

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So when Python tried to execute this line, that

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line called some other things in the script and

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the error was in this line, line two.

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So when the function call tried to call

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the function, it tried to execute this line.

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So if temperature, it tried to compare 5 with 7.

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And then it got this error when

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it tried to compare 5 with 7.

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So when it tried to execute this line, in

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other words, see what it says TypeError.

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This operator is not supported between

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instances of str and int.

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So str and int, which means this was

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a string and this was an int.

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So our user_input was 7, was passed

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in here, and that was compared with 7.

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It seems that our input, the user_input was a string.

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And that is true. And that was the point I was trying to make here.

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Because whatever input the user writes in

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here, even if it's a number, Python

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will actually convert it to a string.

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So 7 in fact, will be converted to a

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string like with quotes or double quotes inside Python.

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But that has an easy fix.

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What you can do is you can convert this

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[Author typing]

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value, which

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is a string seven, you can convert it into a float.

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Be careful with parentheses.

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So float is a function.

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It has an open parentheses in here and

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it has a closing parentheses in here.

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input is also a function with

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its own opening and closing parentheses.

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So now if I do that, Enter temperature

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5, I'm going to get the correct answer.

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And let me be transparent with you.

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Let's again input, get user_input.

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Enter some input.

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Let me now print out the type of user_ input.

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Execute, enter 6.

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You'll see that 6 actually is a string.

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That's why I am converting it into a float.

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So that 6 this time will be

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a float actually, which looks like this.

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You can print out the actual number here, the

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actual converted number, the float version of the number.

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Execute again, 6.

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So 6.0, you can also use Int here if you like.

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[Author typing]

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6, so you'll get 6, which is equal to 6.0, of course.

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But float would be a better choice

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because, I can show you why.

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If you enter 6.3, for example, int will

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not be able to convert it because that

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is like doing int("6.3").

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So int will get confused.

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It will not know how to convert that into an integer.

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It does, however, converts 6 if it was

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a simple 6 without a decimal point, float

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will convert both sorry, both 6 and 6.3.

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And that's how you use user input in Python.

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