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So what is going on in this script?

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Let me explain this one line by line.

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Python executes the function definition but it doesn't do anything because it's just a function definition.

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Python does things when it finds a function call such as this one in here.

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So here we are calling the function and the input value for that function will be a Monday temperature

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which is equivalent to this list.

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So this list will go and be stored in this variable.

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So value is equal to this list.

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OK.

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So what happens is that the interpreter will check if the type of that list is dict. If that is true,

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it will execute this line here.

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So it will assign the

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outputs of this expression to the mean variable.

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However this is not true in this case because type of the list is not a dict.

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So python will not execute this line.

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It will go to the next line.

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So if that was not true then it will do this thing here.

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So the men will be equal to the sum of the list divided by the length of the list which is 9.26

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something.

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So this is the current value of the mean.

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Therefore here the indentation ends.

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So return is outside of the if and else block you can see here, it has to be outside.

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So the conditional block ends here and the current value of the mean will be returned by the return

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statement.

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So you get that mean value for

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that list.

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If this was student grades instead what happens is that this dictionary will be stored in value and

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if type of value is dict.

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Yes it's a dict.

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The men will be equal to that.

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So to the mean of the dictionary.

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And if this condition is true this is executed and python will ignore everything that is under else.

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I said everything that is under else which means everything that is indented under else.

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So the children of else

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So to say, return of the mean is not a child of else,
it's not indented under else.

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It's independents.

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It has its own indentation level.

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So therefore the current value of the mean is this one
in here, so return to the mean will actually

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return the mean for the dictionary, that one in there.