Why can’t you directly use the insert method on a list? (see description)

Question

words = ["Python", "fun"]
words.insert(1, 15)
print(words)
print(["Python","fun"].insert(1,15))

Output:
['Python', 15, 'fun']
None

Answer 1

In addition to what Eduardo Petry said, python adds an implicit "return None" to every function that doesn't have an explicit return statement. So technically every function that doesn't return anything will return None, even print():

print(print('hi'))

Output:

> hi
> None

Answer 2

The `insert` function is a procedure you do onto an already existing list and it returns None (does not return the modified list).

Answer 3

Imagine a function add(a, b) that adds two numbers and returns the sum. If you use print(add(5,3)), the return value 8 is printed.

Now imagine another function that does something (like insert something into a list), but doesn't return anything. If you print the function call like this: print(list. insert(position, item)), it will print None because the insert function isn't meant to return anything.

Answer 4

Ohhh I get it now, thanks Anna! 😁

Answer 5

Anna I think I get your example, but how exactly does my last line of code not have a return statement?

Answer 6

python

Answer 7

Roger Wang it's not the last line of your code, it's the last line of the builtin list.insert() function