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Let's cover Dictionaries in Python.

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Dictionaries are a type of collection in Python.

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If you recall, a list is integer indexes.

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These are like addresses.

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A list also has elements.

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A dictionary has keys and values.

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The key is analogous to the index.

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They are like addresses, but they don't have to be integers.

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They are usually characters.

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The values are similar to the element in a list and contain information.

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To create a dictionary,

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we use curly brackets.

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The keys are the first elements.

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They must be immutable and unique.

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Each key is followed by a value separated by a colon.

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The values can be immutable, mutable, and duplicates.

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Each key and value pair is separated by a comma.

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Consider the following example of a dictionary.

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The album title is the key, and the value is the released data.

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We can use yellow to highlight the keys and leave the values in white.

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It is helpful to use the table to visualize

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a dictionary where the first column represents the keys,

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and the second column represents the values.

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We can add a few more examples to the dictionary.

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We can also assign the dictionary to a variable.

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The key is used to look at the value.

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We use square brackets.

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The argument is the key.

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This outputs the value.

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Using the key of "Back in Black,"

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this returns the value of 1980.

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The key, "The Dark Side Of The Moon,"

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gives us the value of 1973.

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Using the key,"The bodyguard,"

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gives us the value 1992 and so on.

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We can add a new entry to the dictionary as follows.

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This will add the value 2007 with a new key called "Graduation."

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We can delete an entry as follows.

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This gets rid of the key

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"Thriller" and it's value.

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We can verify if an element is in the dictionary using the "in" command as follows:

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The command checks the keys.

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If they are in the dictionary,

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they return a true.

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If we try the same command with a key that is not in the dictionary,

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we get a false.

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In order to see all the keys in the dictionary,

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we can use the method keys to get the keys.

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The output is a list-like object with all the keys.

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In the same way, we can obtain the values using the method values.

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Check out the labs for more examples and info. on dictionaries.