what is the answer for this question?

We're actually not meant to just give away the answers here on the forums. That doesn't help anyone learn.

You should get used to searching for your answers, starting from the official documentation, but you'll often find yourself on sites like Stack Overflow.

Here's a page on the Python docs that should help you find the answer you're looking for:

https://docs.python.org/3/library/functions.html#slice

The slice syntax is composed on a start value, a stop value, and a step value.

The slice syntax is composed on a start value, a stop value, and the increment value.

my_list[start:stop:increment]

So as an example, say you wanted to print the odd numbers from a list of numbers, 1 - 10.

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

my_list[0:9:2] 
# [1, 3, 5, 7, 9]