What is the cleanest way to do a sort plus uniq on a Python list?

Question

Consider a Python list my_list containing [\'foo\', \'foo\', \'bar\'].

What is the most Pythonic way to uniquify and sort a list ?
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Answer 1

Others have mentioned sorted(set(my_list)), which works for hashable values such as strings, numbers and tuples, but not for unhashable types such as lists.

To get a sorted list of values of any sortable type, without duplicates:

from itertools import izip, islice
def unique_sorted(values):
    "Return a sorted list of the given values, without duplicates."
    values = sorted(values)
    if not values:
        return []
    consecutive_pairs = izip(values, islice(values, 1, len(values)))
    result = [a for (a, b) in consecutive_pairs if a != b]
    result.append(values[-1])
    return result

This can be further simplified using the "pairwise" or "unique_justseen" recipes from the itertools documentation.