1 files changed, 1 insertions, 3 deletions
diff --git a/Lib/wsgiref/headers.py b/Lib/wsgiref/headers.py
index 016eb86..934a645 100644
--- a/Lib/wsgiref/headers.py
+++ b/Lib/wsgiref/headers.py
@@ -80,12 +80,10 @@ class Headers:
 
 
 
-    def has_key(self, name):
+    def __contains__(self, name):
         """Return true if the message contains the header."""
         return self.get(name) is not None
 
-    __contains__ = has_key
-
 
     def get_all(self, name):
         """Return a list of all the values for the named field.