Python List insert()

Difficulty Level : Basic
Last Updated : 03 Aug, 2021

The Python List insert() method is an inbuilt function in Python that inserts a given element at a given index in a list.

Syntax:
list_name.insert(index, element)
Parameters:
index: the index at which the element has to be inserted.
element: the element to be inserted in the list.
Returns:

This method does not return any value but it inserts the given element at the given index.
Error:
If anything other than a list is used with insert(), then it returns an AttributeError.
Note:
If given index >= length(list) is given, then it inserts at the end of the list.

Example1: Inserting an Element to the List

Python3

# Python3 program for use  
# of insert() method 
  
list1 = [ 1, 2, 3, 4, 5, 6, 7 ] 
  
# insert 10 at 4th index 
list1.insert(4, 10) 
print(list1) 
  
list2 = ['a', 'b', 'c', 'd', 'e'] 
  
# insert z at the front of the list
list2.insert(0, 'z')
print(list2)

Output:

[1, 2, 3, 4, 10, 5, 6, 7]
['z', 'a', 'b', 'c', 'd', 'e']

Example 2: Error of insert() Method

Python3

# Python3 program for error  
# of insert() method 
  
# attribute error 
string = "1234567"
  
string.insert(10, 1)
print(string)

Output:

Traceback (most recent call last):
  File "/home/2fe54bd8723cd0ae89a17325da8b2eb5.py", line 7, in 
    string.insert(10, 1)
AttributeError: 'str' object has no attribute 'insert'

Example 3: Insertion in a List Before any Element

Python3

# Python3 program for Insertion in a list  
# before any element using insert() method 
  
list1 = [ 1, 2, 3, 4, 5, 6 ]
  
# Element to be inserted 
element = 13 
  
# Element to be inserted before 3
beforeElement = 3 
  
# Find index
index = list1.index(beforeElement) 
  
# Insert element at beforeElement 
list1.insert(index, element) 
print(list1)

Output:

[1, 2, 13, 3, 4, 5, 6]

Example 4: Inserting a Tuple to the List

Python3

list1 = [ 1, 2, 3, 4, 5, 6 ]
  
# tuple of numbers
num_tuple = (4, 5, 6)
  
# inserting a tuple to the list
list1.insert(2, num_tuple)
  
print(list1)

Output:

[1, 2, (4, 5, 6), 3, 4, 5, 6]

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