diff --git a/tutorial/py.twisted/PythonServer.py b/tutorial/py.twisted/PythonServer.py
index 1b0e2d5..034e4a3 100755
--- a/tutorial/py.twisted/PythonServer.py
+++ b/tutorial/py.twisted/PythonServer.py
@@ -85,6 +85,7 @@
     def zip(self):
         print('zip()')
 
+
 if __name__ == '__main__':
     handler = CalculatorHandler()
     processor = Calculator.Processor(handler)