[issue2334] Backport set comprehensions

[Brett Cannon]

New submission from Brett Cannon <brett at python.org>:

Set comprehensions need to be backported.

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components: Interpreter Core
keywords: 26backport
messages: 63691
nosy: brett.cannon
priority: immediate
severity: normal
status: open
title: Backport set comprehensions
versions: Python 2.6

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