[issue33521] Add 1.32x faster C implementation of asyncio.isfuture().

[STINNER Victor]

Change by STINNER Victor <vstinner at redhat.com>:


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nosy: +vstinner
versions:  -Python 3.6, Python 3.7

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue33521>
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