Skip `has_key` when running 2to3.

setup.py

@@ -269,10 +269,11 b" if 'setuptools' in sys.modules:"
         # so we explicitly disable some 2to3 fixes to be sure we aren't forgetting
         # anything.
         setuptools_extra_args['use_2to3_exclude_fixers'] = [
-                'lib2to3.fixes.fix_except',
                 'lib2to3.fixes.fix_apply',
-                'lib2to3.fixes.fix_repr',
+                'lib2to3.fixes.fix_except',
+                'lib2to3.fixes.fix_has_key',
                 'lib2to3.fixes.fix_next',
+                'lib2to3.fixes.fix_repr',
                 ]
         from setuptools.command.build_py import build_py
         setup_args['cmdclass'] = {'build_py': record_commit_info('IPython', build_cmd=build_py)}