31 Years of Python | 48 Hour Sale Extension!!!

I don't understand the code below. Specifically the traffic[i:i+27]

Screen Link:

My Code:

['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday']
traffic_per_day = {}
for i, day in zip(range(0, 135, 27), days):
    each_day_traffic = traffic[i:i+27]
    traffic_per_day[day] = each_day_traffic

What I expected to happen:

What actually happened:

Replace this line with the output/error

Please make sure to include the link to the Screen as well to provide context so that others can help you out accordingly.

I would also recommend searching for similar questions because I think this is something that has been asked before. When you click on the Community button in the Classroom, it shows the questions that have been asked for that particular lesson. Going through those (especially ones which include a tag corresponding to the lesson and screen numbers) can help you get an answer as well.

Here is the link