diff --git a/lib/tz.py b/lib/tz.py
index a9adcd8f..ec63f6c0 100644
--- a/lib/tz.py
+++ b/lib/tz.py
@@ -63,7 +63,7 @@ class FixedOffsetTimezone(datetime.tzinfo):
         try:
             return cls._cache[key]
         except KeyError:
-            tz = datetime.tzinfo.__new__(cls, offset, name)
+            tz = super(FixedOffsetTimezone, cls).__new__(cls, offset, name)
             cls._cache[key] = tz
             return tz