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In this video you will learn about dictionary in python.

A dictionary is a collection which allows us to use keys (keys are string) to store the elements. The element can be a value, list , tuple or any other object. So dictionary is unordered and changeable collection. The items are stored using keys. These keys are used to access the items stored. We can create dictionary using following methods.
• Using curly brackets: We can create a dictionary using curly brackets.
Example:
mybike={"company":"bajaj","modelname":"pulsar 180 DTSi","mfgyear":2007}
• Using dict () : We can also create a dictionary using dict() constructor. Remember in dict() we write keys without double quotes.
Example:
mybike=dict(company="bajaj",modelname="pulsar 180 DTSi",mfgyear=2007)
Accessing an element
We can access an element of dictionary using dictionary name , square brackets and key.
Example:
print(mybike[“company"])
Note: if you try to access a key which does not exist then it gives KeyError.
We can also use get() method to get the value of a specified key:
print(mybike.get(“company"))
Note: if you try to access a key using get(), which does not exist then get() return None value.
Change an element
We can change the value of existing element using its keyname:
Example:
mybike[‘mfgyear’]=2008
Adding an element
We can easily add an item by assigning value to a new key:
Example:
mybike[‘price’]=90000

Removing an element
We can remove an element by its key using pop() method. If you try to delete a non-existing key then it gives KeyError.
Example:
mybike.pop("price")
We can also remove the last element using popitem() method. It always removes the last element.
Example:
mybike.popitem()
Note: If you call the popitem() on empty dictionary then it gives KeyError.
We can use del operator to delete a element using its key:
Example:
del mybike[‘price’]
Note: if you try to delete a non-existing key then it gives KeyError.
The complete dictionary can be deleted using the del keyword.

Example:
del mybike

We can use clear() function to delete all elements from dictionary. It does not delete the dictionary.

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