python - How to append a list with a single string to a list? -


i wondering how able append list list?

x = [] x.append(list(('h4','h3'))) print x # [['h4', 'h3']]  x.append(list('h4')) print x # [['h4', 'h3'], ['h','4']]

i wondering how [['h4', 'h3'], ['h4']] instead of [['h4', 'h3'], ['h','4']]. scoured web , saw x.extend isn't wanted :\

you can use [] instead of list:

x.append(['h4'])

the list function (which constructs new list) takes iterable in parameter , adds every element of iterable in list. but, strings iterable in python, each element (characters here) added elements in list. using [] shortcut avoid that.

from documentation:

list([iterable])

return list items same , in same order iterable‘s items. iterable may either sequence, container supports iteration, or iterator object. if iterable list, copy made , returned, similar iterable[:]. for instance, list('abc') returns ['a', 'b', 'c'] , list( (1, 2, 3) ) returns [1, 2, 3]. if no argument given, returns new empty list, [].


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