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1,416 PointsWhat's the difference between append and extend in this example?
I don't understand what differentiates append and extend. Is it that append is for one item as a string and extend is for adding multiple items?
2 Answers
Steven Parker
231,236 PointsThe "append" method adds a single item to a list, though the item might be another list. On the other hand, "extend" will add another list as individual items. You can see this in the example you provided:
list1.append(list2)
list1
['a', 'b', 'c', ['d', 'e', 'f']] # list2 is still a list, INSIDE the big list
list1.extend(list3)
list1
['a', 'b', 'c', ['d', 'e', 'f'], 1, 2, 3] # but 1, 2, and 3 are separate in the big list
Happy coding! And for some holiday-season fun and coding practice, give Advent of Code a try!
nicolaspeterson
8,569 PointsWas just about to ask the same question and found your answer. Many thanks.
aaron r
1,669 Pointsif one can extend a list with single list item, why bother with append?
Steven Parker
231,236 PointsYou might want to add something to a list that isn't already in another list.
Dave StSomeWhere
19,870 PointsDave StSomeWhere
19,870 PointsIt is possible that if you try experimenting in your REPL you might get a better understanding of the difference between the two methods.
Something like below could be a good start: