replace has_key with 'in' operator
diff --git a/Lib/idlelib/RemoteDebugger.py b/Lib/idlelib/RemoteDebugger.py
index fa234d1..0b89168 100644
--- a/Lib/idlelib/RemoteDebugger.py
+++ b/Lib/idlelib/RemoteDebugger.py
@@ -230,7 +230,7 @@
         return self._get_dict_proxy(did)
 
     def _get_dict_proxy(self, did):
-        if self._dictcache.has_key(did):
+        if did in self._dictcache:
             return self._dictcache[did]
         dp = DictProxy(self._conn, self._oid, did)
         self._dictcache[did] = dp