http://python.org/

Python is a programming language that lets you work more quickly and integrate your systems more effectively. You can learn to use Python and see almost immediate gains in productivity and lower maintenance costs.

Python Set Types:

A set type is a collection data type that supports the membership operator (in), the size function (len()), and is iterable. In addition, set types at least provide a set.isdisjoint() method, and support for comparisons, as well as support for the bitwise operators (which in the context of sets are used for union, intersection, etc.).

Python provides two built-in set types: the mutable set type and the immutable frozenset.

When iterated, set types provide their items in an arbitrary order.