Kill execfile(), use exec() instead

Lib/pdb.py

@@ -1164,7 +1164,12 @@ see no sign that the breakpoint was reached.
         self._wait_for_mainpyfile = 1
         self.mainpyfile = self.canonic(filename)
         self._user_requested_quit = 0
-        statement = 'execfile( "%s")' % filename
+        fp = open(filename)
+        try:
+            script = fp.read()
+        finally:
+            fp.close()
+        statement = 'exec("%s")' % script
         self.run(statement)
 
 # Simplified interface