Python List insert()

In this tutorial, we will learn about the Python List insert() method with the help of examples.

The insert() method inserts an element to the list at the specified index.

Example

# create a list of vowels
vowel = ['a', 'e', 'i', 'u']

# 'o' is inserted at index 3 (4th position)
vowel.insert(3, 'o')


print('List:', vowel)

# Output: List: ['a', 'e', 'i', 'o', 'u']

1. Syntax of List insert()

The syntax of the insert() method is

list.insert(i, elem)

Here, elem is inserted to the list at the i^th index. All the elements after elem are shifted to the right.

2. insert() Parameters

The insert() method takes two parameters:

• index – the index where the element needs to be inserted
• element – this is the element to be inserted in the list

Notes:

• If index is 0, the element is inserted at the beginning of the list.
• If index is 3, the index of the inserted element will be 3 (4th element in the list).

3. Return Value from insert()

The insert() method doesn’t return anything; returns None. It only updates the current list.

4. Example 1: Inserting an Element to the List

# create a list of prime numbers
prime_numbers = [2, 3, 5, 7]

# insert 11 at index 4
prime_numbers.insert(4, 11)


print('List:', prime_numbers)

Output

List: [2, 3, 5, 7, 11]

5. Example 2: Inserting a Tuple (as an Element) to the List

mixed_list = [{1, 2}, [5, 6, 7]]

# number tuple
number_tuple = (3, 4)

# inserting a tuple to the list
mixed_list.insert(1, number_tuple)


print('Updated List:', mixed_list)

Output

Updated List: [{1, 2}, (3, 4), [5, 6, 7]]