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This function returns the mean value of a list

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but we want to make it more intelligent.

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We want the function to return the mean

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even if the input value is a dictionary.

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So when the input value is a list, it will

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going to apply a specific algorithm and return the specific

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value which is the mean of the list.

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When it's a dictionary, it's going to check if

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it's a dictionary and can apply the corresponding algorithm

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that calculates the mean value of a dictionary.

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So we know that

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[Author typing]

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sum monday_temperatures

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divided by length of monday_temperatures gives

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you the mean of the list.

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Similarly, student_grades which is a dictionary, its values,

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the sum of its values divided by the length

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of student_grades dictionary will give you the mean.

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So we want our function to check and make a decision.

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This is a parameter, let me change it to value.

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[Author typing]

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value is a more meaningful name since what

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we are processing will not only be a

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list, but it can also be a dictionary.

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And then under the function

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everything has to be indented.

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You can see the whole body of the function is indented.

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So the conditional block that I'm going to

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write here is also going to be indented.

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It starts with if.

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If you remember we use a type function earlier in

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the course which returned the type of an object.

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For example, this is a dictionary, an

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empty one, but it's still a dictionary.

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So what you can do here is you can say

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if type value double assignment operator which means equal.

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It's a comparison operator, it checks equality.

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If that is a dict: enter, and

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it has to be indented with four spaces.

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So you see, it's another level of indentation.

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It's one here for if and this is for the function.

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So here the_mean will be equal to sum

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of value.values

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[Author typing]

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divide by the length of value.

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So this is a dictionary, dict.values,

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and length of the dictionary.

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I have to close the sum function call there, like that

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and enter if you are done with the if block.

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So if that's all what you want to check, then you say else

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[No audio]

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and we have this code which has

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to be indented under else as well and that's it.

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Let me try this.

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So with student_grades the dictionary as

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input, we got this value here.

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If I used

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[Author typing]

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the list

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[No audio]

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monday_temperatures, it's

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going to give me the other value which

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is the mean of the monday_temperatures.

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So that's an if and else conditional.

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But let me explain it line by line in the next video.

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[Outro sound]