Extend list with another list in specific index?

In python we can add lists to each other with the extend() method but it adds the second list at the end of the first list.

lst1 = [1, 4, 5]
lst2 = [2, 3]

lst1.extend(lst2)

Output:
[1, 4, 5, 2, 3]

How would I add the second list to be apart of the 1st element? Such that the result is this;

[1, 2, 3, 4, 5 ]

I’ve tried using lst1.insert(1, *lst2) and got an error;

TypeError: insert expected 2 arguments, got 3

>Solution :

For those who don’t like reading comments:

lst1 = [1, 4, 5]
lst2 = [2, 3]

lst1[1:1] = lst2
print(lst1)

Output:

[1, 2, 3, 4, 5]