Perl Primer

In December 2008, the Python consortium released a completely new version of Python, Python 3.0, that is not backward compatible: this means that programs written with Python 1 or Python 2 may not run under Python 3.0. At this stage, we move to Python 3.1.3. If you have Python 2 code, a tool, 2to3, will help you convert most of Python 2.x code ... ................
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