Run 2to3's fix_has_key over distutils.
diff --git a/Lib/distutils/command/install.py b/Lib/distutils/command/install.py
index ffd68db..f1ebcbf 100644
--- a/Lib/distutils/command/install.py
+++ b/Lib/distutils/command/install.py
@@ -347,7 +347,7 @@
                 opt_name = opt[0]
                 if opt_name[-1] == "=":
                     opt_name = opt_name[0:-1]
-                if self.negative_opt.has_key(opt_name):
+                if opt_name in self.negative_opt:
                     opt_name = longopt_xlate(self.negative_opt[opt_name])
                     val = not getattr(self, opt_name)
                 else: