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[no audio]

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Friends, here we are going to

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discuss about scope of the variables for

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your functions.

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So before starting with the scope of the variables, let me

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show you how to call a function from another function.

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So I have taken a script name as 'scope_of_the_variables'.

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Right. Fine.

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Now, what I am doing is I'm going to define a function.

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Let's say simply I'm calling

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'myfunction1'. You can take any function names based on

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your rules.

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Let's say I want to display

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[no audio]

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"Welcome to functions".

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Right. So at the end just try to write 'return None'. That's it.

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Now, I'm going to define one more function, 'myfunction2'.

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[no audio]

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"Thank you".

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Then just write 'return None'. That's it.

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Now you have two functions in your code.

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So to execute, to get the output from your functions, what

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we have to do is, we need to call them, right. Suppose

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I am going to call 'myfunction1'.

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So this is the way how we can call your functions, right. See

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that. You're getting your output from first function.

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Now, if you want to execute your code which is there in second

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function as well, what we have to do

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is, we can call your second function.

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[no audio]

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That's it.

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But sometimes while going forward while writing real-time

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scripts, you may need to call your function from inside of

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another function.

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Yes, you can call it.

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Let's say I want to call 'myfunction2' from 'myfunction1',

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so I am calling from my function.

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[no audio]

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That's it. You're getting your output.

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"Thank you". Right. So from function one, I'm calling function

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two. Yes, you can call any function from any place.

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Right. Fine.

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Now, what I am doing is, and one more thing guys, if you observe,

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now this function is in your 'main' code, right?

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If you observe it is outside of your function.

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[no audio]

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But while going forward in your real time, right, maximum

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cases we won't write any logic outside of a function each and

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everything even suppose sometimes if you have a single line

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we'll try to write that line in terms of a function.

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That's a good practice, right?

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That's fine.

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[no audio]

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Now see that, what I am doing is, I am writing some 'x=10',

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and I want to print that 'x' value from your function

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one. Let's say, "x value from fun1 :", just I'm trying to

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print 'x' value. At the same time

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let me print the 'x' value,

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[no audio]

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"x value from fun2: ". Yes. Now, let me run it and see the

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output. You are getting your output.

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[no audio]

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Right. Now I am commenting this.

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[no audio]

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And in function one, I am defining 'x = 10'. Not only

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10, you can take any value.

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Let's say, 60. Now see the result.

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Observe the output. From your function one you are getting

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value as 60, but while executing from function two you are

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getting an error called, name 'x' is not defined.

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So this is called scope of the variables, means if any variable

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is defined inside of a function, by default that variable

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is specific to that function only. You can't access that variable

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outside of that function.

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So I defined 'x = 60' here, and I'm trying to display 'x'

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value from your second function.

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It won't work.

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It is specific to this function, or this is a local variable

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for this function.

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But if you observe, previously we did this one, right. Let's

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say first, let me comment this.

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[no audio]

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Whenever if any variable is

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defined outside of a function that variable you are able

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to access from function 1 and function 2. That means if any

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variable is defined outside of a function, then that is

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global variable.

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So by default if you define any variable outside of a function,

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see nowhere we have here,

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we don't have any function here, right?

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We are calling, but 'x = 10' in the 'main' code, it is not

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under any function. Then this 'x' is by default global variable.

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Global variable means, you can access that variable anywhere

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inside of your function, inside of your script.

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Right. Now what we are doing.

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If any variable is defined inside of a function, then that

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variable is specific to your function only.

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Right, now we have two types of variables, local and global variables.

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Right. First thing, scope means this is the meaning for your scope

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of the variable.

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So based on this scope, we have local and global variables.

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Now I can say this is a global variable.

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[no audio]

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And now if I enable this. Let's say this is local.

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[no audio]

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Now I'm running. See the result what you are getting.

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[no audio]

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So in 'main' code I have taken 'x = 10', and in 'myfunction1'

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I am defining 'x = 60'. Now, whenever if we take same

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variables in the 'main' code, and in the function, they are

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not same. Now this 'x' is different, and this 'x' is different.

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That's why while executing from 'myfunction1',

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what is the result you are getting? 60 value, because

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you defined 60 here.

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But from function two we don't have any 'x' variable here, then

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what your Python will do means,

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is there any global variable related with 'x', then we'll try to

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print that 'x', but before that in case if we have a local variable,

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now see the result, you are getting 40.

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So your function will give, your Python will give priority

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for your local variables inside of your function

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while trying to display your 'x' variable value. If 'x' is not

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defined inside of your function,

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I mean, if no local variable 'x', then what your Python will

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do means, it will try to find is there any 'x' as a global variable?

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If it is there you will try to print that variable value.

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If it is not there, then it will throw an error. See that, now

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I am commenting 'x = 10' in your 'main' code.

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Now you're getting an error.

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That's it. So this is simply scope of the variables.

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[no audio]

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Right, and last one,

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let me explain that. Now while going forward, right,

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we are going to write each and everything in terms of functions

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only. Now what I will do is,

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[no audio]

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you can take any function, not

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only 'main', but if we take 'main' then somewhat meaningful that's

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it. 'main' means

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your code will start from this place. That's it.

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Other than that nothing is there.

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[no audio]

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Defining 'x = 10', and calling 'myfunction1',

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I'm also taking as under one function, right. Now,

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if I run this there is no output because you defined three

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functions, and nowhere you are calling the execution point

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from where you want to start your code, whether you want to

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start from function 2, or function 1, or from main function,

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from which place you want to execute your code. As of now,

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right, I am feeling that this is my 'main' code. I have to start

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execution from this point, that's why I need to call this

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function somewhere.

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So now I am calling 'main'.

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[no audio]

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That's it.

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Now, whenever if you are trying to call in this way, you're

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getting an error called, name 'x' is not defined, from your

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'main', in which function? 'myfunction2'.

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[no audio]

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Right. Now, what I want to do is, as of now if you observe 'x = 10'

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is not a global variable, right?

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This is under, let me delete this.

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Now, this is under the 'main' function. 'main' is also one function

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like 'myfunction'.

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So instead of 'main' you can also take 'mycodestartsfromhere'.

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[no audio]

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You can take anything, but just we are following. Now

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we have to right here, instead of 'main' you have to write

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this one. That's it.

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Now see the result. Same thing.

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[no audio]

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So instead of this, just generally all are following like

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this. 'main', that's it. Now, instead of this, 'main'. Right. 'main' is

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also like one function.

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Now if you observe inside of your 'main', 'x = 10' is there.

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Now, this is a function, right. Now 'x = 10' is local, local

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for this 'main' function.

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You can't access now 'x = 10' from outside of your function,

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'main' function, or any of your functions.

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I defined 'x = 60',

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that's why from my 'myfunction1'.

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I can able to access 'x = 60', but in 'myfunction2' I

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don't have 'x' value. Then how can I get it?

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That's why you're getting an error. Now whatever the variable

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is there in 'main' function, 'x = 10', that variable

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value I want to access from 'myfunction2'. Then how? In case

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if it is there here, then that is the 'main' function,

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I mean in main logic you have, now you're getting your 'x' value

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from function 2 as 10, but now 'x = 10' is there in 'main'

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function, but I want to access this 'x = 10' from 'myfunction2'.

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[no audio]

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Right. Then in 'main' function,

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I mean whatever the function you have, in that function you

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have to write 'global x'.

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That means now 'x' is global.

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You can access my 'x' variable anywhere inside of your Python

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Script. Now see the result. Now you're getting from function 2, 10.

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[no audio]

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Fine. But guys making your variable as global is not always good.

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Okay. Sometimes you can take it as a, variable as global,

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but instead of global we have one more way to pass your

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corresponding variable to your required function.

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Right. See that. Now, I am going to comment from here.

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[no audio]

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Don't get confused,

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okay. We'll discuss this again in next video. As of now just

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I am giving the way how you can pass. See now

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I'm going to comment this, and as of now if I run my code

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what you are getting?

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From 'myfunction1' you are getting your value as 60. Now,

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I'm not calling anywhere 'myfunction2'. Now, I want to call

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'myfunction2', suppose from 'main' function itself.

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Now I am calling, but in 'myfunction2' I don't

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have any variable called 'x',

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that's why we are getting an error.

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I don't want to use global. In case if I use global,

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yes, it will work without an error, but I don't want to use

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variable as a global.

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But I want to send the value of, 'x' value 10 to 'myfunction2',

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so other way to pass your value to your required function

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is just inside of your parentheses,

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just write 'x'.

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[no audio]

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Now here also you have to write

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'x'. Now what will happen? The 10 value, while calling this

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'myfunction2' you are also passing, not 'x', you are not passing

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'x'. The value of 'x', 10, 10 you are passing.

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So the meaning for this is, you are not passing 'x', value of

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'x', 10 you're passing to this variable. Now this 'x' and this

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'x', they are completely different. In case if you are

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having a confusion,

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right, first let me run it and see the result.

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Now what I am doing, instead of 'x', I'm taking 'y'. Now,

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I want to print that 'y'.

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That's it.

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Right. So other than global, how can you, if I take global

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then this variable is,

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you can access that variable from any function, from any line

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anywhere in your Python Script. But I don't want to access

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in all places, only from this function only.

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I want to access this variable 'x', that value, not even that

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'x', only the value of 'x', then I can send in this way.

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That's it. And one more important point is, now this variable and this

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variable are completely different. The value of 'x' will be assigned

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to 'y', that value we are printing.

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That's it. Okay.

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So now here, whenever if you pass your variable to your function,

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then that is called argument.

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And here that is called

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parameter. Okay. We will discuss in detail in the next video

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about this argument and parameter, okay.

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Okay guys, thank you for watching this video.

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