10.6: List methods
- Page ID
- 40785
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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') >>> 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) >>> 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() >>> t ['a', 'b', 'c', 'd', 'e']
Most list methods are void; they modify the list and return None
. If you accidentally write t = t.sort()
, you will be disappointed with the result.