Modernize code to Python 3.6+ and some cleanup

09-closure-deco/average.py

@@ -28,6 +28,6 @@ def make_averager():
     def averager(new_value):
         series.append(new_value)
         total = sum(series)
-        return total/len(series)
+        return total / len(series)
 
     return averager

09-closure-deco/average_oo.py

@@ -10,7 +10,7 @@
 """
 
 
-class Averager():
+class Averager:
 
     def __init__(self):
         self.series = []

09-closure-deco/fibo_demo.py

@@ -5,7 +5,7 @@ from clockdeco import clock
 def fibonacci(n):
     if n < 2:
         return n
-    return fibonacci(n-2) + fibonacci(n-1)
+    return fibonacci(n - 2) + fibonacci(n - 1)
 
 
 if __name__ == '__main__':

09-closure-deco/fibo_demo_lru.py

@@ -8,7 +8,7 @@ from clockdeco import clock
 def fibonacci(n):
     if n < 2:
         return n
-    return fibonacci(n-2) + fibonacci(n-1)
+    return fibonacci(n - 2) + fibonacci(n - 1)
 
 
 if __name__ == '__main__':