Python List of Dictionaries

List of Dictionaries in Python

In Python, you can have a List of Dictionaries. You already know that elements of the Python List could be objects of any type.

In this tutorial, we will learn how to create a list of dictionaries, how to access them, how to append a dictionary to list and how to modify them.

Create a List of Dictionaries in Python

In the following program, we create a list of length 3, where all the three elements are of type dict.

Python Program

myList = [
	{
		'foo':12,
		'bar':14
	},
	{
		'moo':52,
		'car':641
	},
	{
		'doo':6,
		'tar':84
	}
]

print(myList)

Output

[{'foo': 12, 'bar': 14}, {'moo': 52, 'car': 641}, {'doo': 6, 'tar': 84}]

Each element of the list is a dictionary.

Access key:value pairs in List of Dictionaries

Dictionary is like any element in a list. Therefore, you can access each dictionary of the list using index.

And we know how to access a specific key:value of the dictionary using key.

In the following program, we shall print some of the values of dictionaries in list using keys.

Python Program

myList = [
	{
		'foo':12,
		'bar':14
	},
	{
		'moo':52,
		'car':641
	},
	{
		'doo':6,
		'tar':84
	}
]

print(myList[0])
print(myList[0]['bar'])

print(myList[1])
print(myList[1]['moo'])

print(myList[2])
print(myList[2]['doo'])

Output

{'foo': 12, 'bar': 14}
14
{'moo': 52, 'car': 641}
52
{'doo': 6, 'tar': 84}
6

Update key:value pairs of a Dictionary in List of Dictionaries

In the following program, we shall update some of the key:value pairs of dictionaries in list: Update value for a key in the first dictionary, add a key:value pair to the second dictionary, delete a key:value pair from the third dictionary.

Python Program

myList = [
	{
		'foo':12,
		'bar':14
	},
	{
		'moo':52,
		'car':641
	},
	{
		'doo':6,
		'tar':84
	}
]

#update value for 'bar' in first dictionary
myList[0]['bar'] = 52

#add a new key:value pair to second dictionary
myList[1]['gar'] = 38

#delete a key:value pair from third dictionary
del myList[2]['doo']

print(myList)

Output

[{'foo': 12, 'bar': 52}, {'moo': 52, 'car': 641, 'gar': 38}, {'tar': 84}]

Append a Dictionary to List of Dictionaries

In the following program, we shall append a dictionary to the list of dictionaries.

Python Program

myList = [
	{
		'foo':12,
		'bar':14
	},
	{
		'moo':52,
		'car':641
	},
	{
		'doo':6,
		'tar':84
	}
]

#append dictionary to list
myList.append({'joo':48, 'par':28})

print(myList)

Output

[{'foo': 12, 'bar': 14}, {'moo': 52, 'car': 641}, {'doo': 6, 'tar': 84}, {'joo': 48, 'par': 28}]

Summary

In this tutorial of Python Examples, we learned about list of dictionaries in Python and different operations on the elements of it, with the help of well detailed examples.

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