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README.md

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+Overview
+========
+
+`auto2to3` is a wrapper to run `2to3` automatically at import time.  This is
+useful when developing a library that intends to support both Python 2 and
+Python 3 via `2to3`.  
+
+Usage
+=====
+
+`auto2to3.py --package=pkg main_module`
+
+main_module is run as if by the -m flag to the python interpreter
+(i.e. __name__ == '__main__').  All modules whose name begins with a name
+passed to the --package flag (which may be specified more than once)
+will be run through 2to3.  2to3 output is cached on disk between runs
+for speed.
+
+Example
+-------
+
+`auto2to3.py --package=tornado tornado.test.runtests`
+
+Acknowledgements
+================
+
+Based on auto2to3.py by Georg Brandl:
+http://dev.pocoo.org/hg/sandbox/file/tip/auto2to3.py