Checking compatibility of a script across Python versions automatically

[Andrew Berg]

Are there any tools out there that will parse a script and tell me if it
is compatible with an arbitrary version of Python and highlight any
incompatibilities? I need to check a few of my scripts that target 3.2
to see if I can make them compatible with 3.0 and 3.1 if they aren't
already. I found pyqver, but it isn't accurate (at least for 3.2/3.3
scripts) and hasn't been updated in 2 years. I could look over the docs
and do it manually, but one of the scripts isn't small, so I'd prefer
not to.
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CPython 3.3.0a4 | Windows NT 6.1.7601.17803