List methods

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Python provides methods that operate on lists. For example, append adds a new element to the end of a list:

>>> t = ['a', 'b', 'c']>>> t.append('d')>>> print t['a', 'b', 'c', 'd']

extend takes a list as an argument and appends all of the elements:

>>> t1 = ['a', 'b', 'c']>>> t2 = ['d', 'e']>>> t1.extend(t2)>>> print t1['a', 'b', 'c', 'd', 'e']

This example leaves t2 unmodified.

sort arranges the elements of the list from low to high:

>>> t = ['d', 'c', 'e', 'b', 'a']>>> t.sort()>>> print t['a', 'b', 'c', 'd', 'e']

List methods are all void; they modify the list and return None. If you accidentally write t = t.sort(), you will be disappointed with the result.