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fahad lashari
7,693 PointsHow is this any different from list.append()?
Just wondering as I had completed the python collections not long ago
Michal Janek
Front End Web Development Techdegree Graduate 30,654 Pointswhat should be different from list.append()? He is stating that some of these were already mentioned in Python Basic course.
fahad lashari
7,693 PointsHi I am talking in regards to where he used += to add things into the list. Just wondering why he would use that instead of append and extend.
kind regards
2 Answers
Steven Parker
231,275 PointsIt depends on what you are adding to the list.
For single items, .append(), .extend(), and += all do the same thing.
But if the item being added is another list, there's a difference. Both .extend() and += will add the elements from the new list onto the other, but .append() will add the entire new list as a single element onto the other list.
Say for example, you had two lists each with 3 elements. If you combine them with .append() you will have a list with 4 elements, and the last element will itself be a list of 3 elements. But if you combine them with either of the other methods you will get a list of 6 individual elements.
Dariy Kutelov
Front End Web Development Techdegree Graduate 21,706 PointsIf you use += with double brackets like this: [['string1','string2']], wouldn't it add the new list as single element as well?
Steven Parker
231,275 PointsThe inner list, yes. And the same with extend. Both would still be unwrapping the outer list and adding the elements individually.
Steven Parker
231,275 PointsSteven Parker
231,275 PointsWhat is it you are comparing to list.append()?