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So you are a teacher and you wanted

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to calculate the average grade of your students.

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And we did that using this algorithm here

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and this data structure to store the grades.

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The problem here is you don't

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know which grade is of who.

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So while a list is a good data structure to store

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an array of items, it's not good enough when these

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items have some sort of identity attached to them.

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In that case, you want to use a dictionary.

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[Author typing]

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Let's say student_grades, curly

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brackets, that's the syntax for a dictionary.

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And then you use names of your students, let's

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say Marry, a colon, make some space or no

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space, whatever you prefer, but it's good to have

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a space there to make it more readable.

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And then you write the grade of Marry,

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let's say Sim:8.8

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[Author typing]

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and John

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[Author typing]

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:7.5.

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So the difference between the dictionary and

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the list is the brackets, different brackets.

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And then this is considered an item in a

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dictionary, this is considered an item in a list.

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So items in a dictionary are made of keys, this

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is a key and values, this is a value.

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A list would be more appropriate if we had

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to store, for example, an array of temperature values.

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Let's say Monday had

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these temperatures, monday_temperatures.

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And lastly, how do we calculate the

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average when we have a dictionary?

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Since these are pairs of keys and values,

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you can't just make the sum like that.

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You need to specify the sum of what you want to get.

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So student_grades and if you check dir(dict)

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for dictionary, you'll see that dictionaries have these values,

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which is a method, dict.values, it is a

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method and it provides a view of dictionary values.

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In simple words, it gives you

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the values of a dictionary.

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So if you get this dictionary Q for quit

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here, paste it here and see student_grade values

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that will give you this data type.

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So it's still a data type.

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It does look like a list, it's not exactly a list,

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but it behaves like a list with these three values there.

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So it's a dict values type.

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That method produces this type and therefore

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you can add that in there.

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Don't forget the parentheses, don't forget to save and

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don't forget to execute to get the output.

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And this is the average value of the dictionary values.

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To get the keys of dictionary, just do keys, and

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you get this dict keys type with the keys of

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the dictionary as items of that dict keys array.

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[Outro sound]