You can access the items of a dictionary by referring to its key name, inside square brackets:
Get the value of the "model" key:
thisdict = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = thisdict["model"]
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There is also a method called get()
that will give you the same result:
The keys()
method will return a list of all the keys in the dictionary.
The list of the keys is a view of the dictionary, meaning that any changes done to the dictionary will be reflected in the keys list.
Add a new item to the original dictionary, and see that the keys list gets updated as well:
car = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = car.keys()
print(x) #before the change
car["color"] = "white"
print(x) #after the change
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The values()
method will return a list of all the values in the dictionary.
The list of the values is a view of the dictionary, meaning that any changes done to the dictionary will be reflected in the values list.
Make a change in the original dictionary, and see that the values list gets updated as well:
car = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = car.values()
print(x) #before the change
car["year"] = 2020
print(x) #after the change
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Add a new item to the original dictionary, and see that the values list gets updated as well:
car = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = car.values()
print(x) #before the change
car["color"] = "red"
print(x) #after the change
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The items()
method will return each item in a dictionary, as tuples in a list.
The returned list is a view of the items of the dictionary, meaning that any changes done to the dictionary will be reflected in the items list.
Make a change in the original dictionary, and see that the items list gets updated as well:
car = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = car.items()
print(x) #before the change
car["year"] = 2020
print(x) #after the change
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Add a new item to the original dictionary, and see that the items list gets updated as well:
car = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
x = car.items()
print(x) #before the change
car["color"] = "red"
print(x) #after the change
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To determine if a specified key is present in a dictionary use the in
keyword:
Check if "model" is present in the dictionary:
thisdict = {
"brand": "Ford",
"model": "Mustang",
"year": 1964
}
if "model" in thisdict:
print("Yes, 'model' is one of the keys in the thisdict dictionary")
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