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

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.

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

1 Answer

Stuart Wright
Stuart Wright
41,118 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:




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


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: