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Hello and welcome to this video.

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In this video I'm going to introduce you to the Python data type code dictionary.

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What is a Python dictionary.

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A real life dictionary holes words and their meanings.

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A Python dictionary is similar but it holds key value pairs key value pairs.

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Basically mean all the values inside the dictionary will have a unique key and a corresponding value.

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For example you could have a key that is called fruit and the value would be in name of a fruit.

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For example Apple.

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So that's what it means by key value pairs.

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So they come in pairs.

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You have the key and then you have the values.

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The values can be changed.

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That means they are mutable.

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Also the values must have unique keys so you cannot have duplicate keys for the same values.

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The keys are unique.

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You can also store mixed data types so you can store Strings and you can also store numbers inside a

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dictionary.

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You can mix the data types or you can have a specific data type.

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There are different ways you can create a dictionary.

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So let me walk you through a couple of ways.

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I'm going to be using the text editor called atm and I've created an empty file on my desktop called

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My dict and I'll call it my dict dot P Y.

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So any code right here will be a python file.

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First you need to do is give your dictionary a name.

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Try to give it a name that reflects what it is you are storing.

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So I'm going to call my dictionary my car and then R equals 2 and then I'll add my curly braces on our

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top in between to separate the curly braces and I will start adding the key.

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So I stuck with the key first.

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So the key are typing brand and after the key do a column and I then specify the value.

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So my value I'll say Range Rover sports OK.

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That is one key value.

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This is the key which is unique.

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And this is a value the value can change.

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But the key has to be unique for each value someone to tap and add another.

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So you need to separate each of the key value pairs with a comma.

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So had a comma come down here and do a different one.

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So add another key this time I'm going to give this a model make this model and I will add the colon

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and give it a value the fairly how say h s e the comma now had one more key value this time.

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Who's going to make this one the year.

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Make it in lower case.

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Yeah and then the colon and I'll add the year I'll say 2017.

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Notice this is a numerical data type so I don't need to put quotes around it and I don't need to add

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a comma because that is the last value.

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So no need I'm adding more than I use a comma to separate each key value pair.

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So that is basically it for creatine addiction or I've just created a basic dictionary so if I wanted

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to print this dictionary all I have to do is type in print and in parentheses I specify the name of

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my dictionary which is called my car and I'll save my document to control s to save it and then I'll

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run it inside my terminal or command prompt so I've got my command prompt here and I've navigated to

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my desktop which is where my Python far less and that's the name of the file.

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So if I just press enter it should execute the code.

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You can see here is printed out my dictionary.

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That is the key.

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That's the value.

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That's another key that's value.

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That's another key.

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That is the value.

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Another way you can create a dictionary is by using a dictionary constructor function the constructor

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is basically a special function that you can use to create an object.

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So to create a dictionary using the constructor method you first of all have to give the dictionary

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names.

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I'm going to call mine my my greens and you do the equals to type in the word dict.

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Okay and then in parentheses you then specify the key and then the values.

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So this is how you do it.

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If that's for typing the key is a bit different when you use a constructor method.

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So you use the key and then once you specify the key you are the equals two and then you enclose the

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values in quotes.

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If it's a string values I'm going to say green apples.

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Okay so that is one of the comma.

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Now add another key.

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The key this time is going to be virtually tables.

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Okay.

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That's the key.

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And our two equals two.

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And then I'll add value.

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I'm going to enclose that in quotes as well.

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And the value will be kale I can add a print function and then print out what's inside this new dictionary

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are created.

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All I need to do is just pass in the name of the dictionary and I'll save the file and open up my command

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prompt.

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That's my command prompt so I just type in the name.

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You can see here that is my first dictionary.

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This is the second dictionary I created using the constructor function.

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So that's basically how you create dictionaries.

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That's it for this video.

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Thanks for watching.