How to create nested list in Python

In Python, you can create a nested list by placing one or more lists inside another list. This allows you to represent a hierarchical structure or store multiple levels of data.

To create a nested list in Python, you can use the following syntax:

nested_list = [ [element1, element2, ...], [element3, element4, ...], ... ]

Here’s an example of creating a nested list with three inner lists:

nested_list = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

You can also create an empty nested list and then append inner lists to it. Here’s an example:

nested_list = []
nested_list.append([1, 2, 3])
nested_list.append([4, 5, 6])
nested_list.append([7, 8, 9])

Create a nested list in Python example

Here are a few examples of creating nested lists in Python:

Example 1: A nested list of strings

nested_list = [['apple', 'banana', 'cherry'],
               ['orange', 'grapefruit'],
               ['strawberry']]

print(nested_list)

Output:

Example 2: A nested list of mixed data types

nested_list = [[1, 'apple', True], 
               ['banana', 2.5, False], 
               [3, 'cherry', True]]

Example 3: A nested list of lists

nested_list = [[1, 2, 3], [4, 5, 6, 7], [8, 9]]

Example 4: Creating an empty nested list and appending inner lists

nested_list = []
nested_list.append([1, 2, 3])
nested_list.append(['apple', 'banana', 'cherry'])
nested_list.append([True, False])

Example 5: A nested list with duplicate elements

nested_list = [[1, 1, 1], [2, 2, 2], [3, 3, 3]]

The structure and elements of a nested list can vary based on your specific requirements.

Do comment if you have any doubts or suggestions on this Python list topic.

Note: IDE: PyCharm 2021.3.3 (Community Edition)

Windows 10

Python 3.10.1

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.