The difference of list methods between append() and extend() in Python

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Python lists are mutable, you can add objects to the list in place. Both append() and extend() methods could do the trick.

append(): add a single object to the end of the list

>>> l = ['a', 'b', 'c']

>>> l.append(['d','e','f'])

>>> l

['a', 'b', 'c', ['d', 'e', 'f']]

extend(): add all the elements from the iterable to the end of the list

>>> l.extend(['d','e','f'])

>>> l

['a', 'b', 'c', 'd', 'e', 'f']



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