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Python Python Collections (2016, retired 2019) Lists Combining Lists

combining lists task 2

I am getting this error message: "Bummer! best doesn't have five items in it!" Even though the list should have 5 items...

best = ["rock", "wood", "metal"]
best + ["water", "fire"]

2 Answers

Hassaan Ahmad
Hassaan Ahmad
1,979 Points

Hey, you aren't storing the new list into anything. That's why it is giving an error. The += notation adds the new list into best and stores the result in best. It is kind of updating the list.

Hassaan Ahmad
Hassaan Ahmad
1,979 Points

Yeah, that works fine too.