Python Nested Dictionary

Prerequisite – Python dictionary

A Dictionary in Python works similar to the Dictionary in the real world. Keys of a Dictionary must be unique and of immutable data type such as Strings, Integers and tuples, but the key-values can be repeated and be of any type.

Nested Dictionary: Nesting Dictionary means putting a dictionary inside another dictionary. Nesting is of great use as the kind of information we can model in programs is expanded greatly.

Creating a Nested Dictionary

In Python, a Nested dictionary can be created by placing the comma-separated dictionaries enclosed withing braces.

Output:

Nested dictionary 1-
{'Dict1': {}, 'Dict2': {}}

Nested dictionary 2-
{'Dict1': {'name': 'Ali', 'age': '19'}, 'Dict2': {'name': 'Bob', 'age': '25'}}

Nested dictionary 3-
{'Dict1': {1: 'G', 2: 'F', 3: 'G'}, 'Dict2': {1: [1, 2], 'Name': 'Geeks'}}

Adding elements to a Nested Dictionary

Addition of elements to a nested Dictionary can be done in multiple ways. One way to add a dictionary in the Nested dictionary is to add values one be one, Nested_dict[dict][key] = 'value'. Another way is to add the whole dictionary in one go, Nested_dict[dict] = { 'key': 'value'}.

Output:

Initial nested dictionary:-
{}

After adding dictionary Dict1
{'Dict1': {'age': 21, 'name': 'Bob'}}

After adding dictionary Dict1
{'Dict1': {'age': 21, 'name': 'Bob'}, 'Dict2': {'age': 25, 'name': 'Cara'}}

Access elements of a Nested Dictionary

In order to access the value of any key in nested dictionary, use indexing [] syntax.

Output:

Ali
25

Deleting dictionaries from a Nested Dictionary

Deletion of dictionaries from a nested dictionary can be done either by using del keyword or by using pop() function.

Output:

Initial nested dictionary:-
{'Dict2': {'name': 'Bob', 'age': 21}, 'Dict1': {'name': 'Ali', 'age': 19}}

Deleting Dict2:-
{'Dict1': {'name': 'Ali', 'age': 19}}

Deleting Dict1:-
{}