Python list | insert()

insert() 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 then 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.

Code #1 :

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# 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) 

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Output :


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



 

Code #2 :











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# Python3 program for error   


# of insert() method  


  


# attribute error  


string = "1234567"


  


string.insert(10, 1) 


print(string)  



















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Output :


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



 


Practical Application : 

Insertion in a list before any element :


Code #3 : 











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# 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) 



















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Output :


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




          
          
          
          

            

    

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