Here is how to understand how slice notation works in Python.


# Extract a sublist containing the last three items of a list
my_list = [1, 2, 3, 4, 5]
last_three = my_list[-3:]  # This would return [3, 4, 5]

# Extract a sublist containing every other item of a list, starting with the second item
my_list = [1, 2, 3, 4, 5]
every_other = my_list[1::2]  # This would return [2, 4]

# Extract a sublist containing the first three items of a string
my_string = "Hello, world!"
first_three = my_string[:3]  # This would return "Hel" 

Output

 


Explanation

In Python, the slice notation is a way of accessing a part of a string, list, or tuple. The syntax for the slice notation is start:end:step, where start is the starting index, end is the ending index, and step is the number of items to skip between items in the sliced sequence. For example, if you have a list my_list = [1, 2, 3, 4, 5] and you want to extract a sublist that contains the second and third items, you could use the following slice notation: my_list[1:3], which would return the list [2, 3].




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