diff --git a/pyspectator/temperature_reader.py b/pyspectator/temperature_reader.py
index b5d043b..54c84b1 100644
--- a/pyspectator/temperature_reader.py
+++ b/pyspectator/temperature_reader.py
@@ -46,7 +46,7 @@ def reader(file):
 class WindowsCpuTemperatureReader():
 
     @classmethod
-    def get_reader():
+    def get_reader(cls):
         import wmi
         import pythoncom