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pythonlistdata-structuresappendextend

What is the difference between Python's list methods append and extend?


What's the difference between the list methods append() and extend()?


Solution

  • .append() appends a single object at the end of the list:

    >>> x = [1, 2, 3]
    >>> x.append([4, 5])
    >>> print(x)
    [1, 2, 3, [4, 5]]
    

    .extend() appends multiple objects that are taken from inside the specified iterable:

    >>> x = [1, 2, 3]
    >>> x.extend([4, 5])
    >>> print(x)
    [1, 2, 3, 4, 5]