[Tutor] key parameter in sorted

[Peter Otten]

Peter Otten wrote:

> Manprit Singh wrote:

>> lx = [2, 5, 4, 6, 4, 2, 3, 6]
>> sorted(set(lx), key=lx.index)

Another option:

>>> def unique(items):
...     seen = set()
...     for item in items:
...         if item not in seen:
...             yield item
...             seen.add(item)
... 
>>> list(unique(lx))
[2, 5, 4, 6, 3]