Add Items to a List in Python

Here are the 4 most common ways to add items to a list in Python:

(1) Using append() method

The append() method adds a single element to the end of the list.

For example:

my_list = [5, 10, 15]

# Add item to the end of the list
my_list.append(20)
print(my_list) # Output: [5, 10, 15, 20]

(2) Using insert() method

The insert() method adds an element to the specified index within the list.

For example:

my_list = [5, 10, 15]

# Insert element at the beginning of the list
my_list.insert(0, 20)
print(my_list) # Output: [20, 5, 10, 15]

Indices in Python start at the position 0. Therefore the first item is at the index 0, the second item at the index 1 and so on.

(3) Using extend() method

The extend() method adds all elements from an iterable (like another list or tuple) to the end of the list.

For example:

my_list = [5, 10, 15]

# Add elements from another list to the end of the list
my_list.extend([20, 25, 30])
print(my_list) # Output: [5, 10, 15, 20, 25, 30]

(4) Using + operator (concatenation)

The + operator creates a new list by concatenating two or more lists.

my_list = [5, 10]

# Create a new list by concatenating two lists
new_list = my_list + [15, 20]
print(new_list) # Output: [5, 10, 15, 20]

The + operator doesn’t modify the original list. It concatenates two lists to create a new list.

Choosing the right method

Use append() to add a single element to the end of the list.

Use insert() to insert an element at a specified position within the list.

Use extend() to add multiple elements from an iterable (such as another list, or tuple) to the end of the list.

Use + to combine multiple lists or keep the original list unchanged.