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

Posted by princess mudyahoto
princess mudyahoto
18,502 Points

python collections

Challenge Task 2 of 3

Using .extend(), .append(), or +, add two new items onto the end of best. Again, the items can be anything you want.

lists.py 
best = [1,2,3]
best.append = (4,5)

1 Answer

Stuart Wright
Stuart Wright
41,120 Points
Stuart Wright
Stuart Wright
41,120 Points

Note that both .append() and .extend() change the list in place and return None, so you shouldn't use = to assign the result to a variable. You can just use the following syntax:

my_list.append(new_value)

or

my_list.extend(other_list)

.append() can just append a single value. You need to use .extend() if you want to complete this challenge in one line of code:

best.extend([4,5])

Note that in the above statement you are passing a new list (including the []) to the extend method.

If you want to use .append() instead, it will need two lines:

best.append(4)
best.append(5)