Initialize an empty list with certain size in Python

In this tutorial, we are going to learn about how to intialize or create an empty list with certain size in Python.

Empty list means list doesn’t contain any values in it, so the length of empty list is 0.

But we need to create an empty list with certain size.

Using square brackets [] notation

To initialize a empty list with certain size, we can use the square brackets notation with [None] * n in Python.

Here is an example of empty users list with size 5:

users = [None] * 5

print(users)

Output:

[None, None, None, None, None]

The above code will create a list of size 5, where each position in list is initialized to None value.

After that, you can add elements to the list like this:

users[1] = 10

Output:

[None, 10, None, None, None]

To check the length of the list, we can use the len() function in Python.

users = [None] * 5

length = len(users)
print(length)

Output:

5