satisfy pycodestyle checker

src/StructuredDataObject.py

@@ -4,13 +4,12 @@ from AbstractDataObject import AbstractDataObject
 
 
 class StructuredDataObject(AbstractDataObject):
-
     def __init__(self, topicPart):
         super().__init__(topicPart)
         self.keyValuePairs = []
-    
+
     def add(self, key, value):
         self.keyValuePairs.append({key: value})
 
     def getPayload(self):
-        return json.dumps(self.keyValuePairs)
+        return json.dumps(self.keyValuePairs)