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

Posted by kristianemil
kristianemil
4,632 Points

Come on! This should be correct, right?

adding to a list

lists.py 
best = ["cat", "dog", "bird"]
best.append("fish", "dino")

1 Answer

james south
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.a{fill-rule:evenodd;}techdegree seal-36
james south
Front End Web Development Techdegree Graduate 33,271 Points
james south
.a{fill-rule:evenodd;}techdegree seal-36
james south
Front End Web Development Techdegree Graduate 33,271 Points

append takes exactly one argument so you're getting an error. the extend method would do what you are trying to do, but the argument needs to be a list, so add [] around the items. you can append a list to a list, but it will add only one element to the list, which will itself be a list, so you'll have a nested list. extend will "flatten" the added list resulting in a non-nested list with a length equal to the sum of the number of elements in the two lists.

kristianemil
kristianemil
4,632 Points

Thank you so much for your comprehensive response James. I tried the .append method in my personal Python Terminal, and it seemed to work. But in Workspaces – not so much. I solved it though, with the:

best += ["fish", "dino"]

It seemed to do the trick!