Add a useful way to understand python decorator

source_code/learning/decorator.py

@@ -0,0 +1,19 @@
+#!/bin/python
+#
+# An example of Python Decorator
+#
+
+def pretty_sumab(func):                                                                                     
+    def inner(a,b):                                                                                         
+        print(str(a) + " + " + str(b) + " is ", end="")                                                     
+        return func(a,b)                                                                                    
+                                                                                                            
+    return inner                                                                                            
+                                                                                                            
+@pretty_sumab                                                                                               
+def sumab(a,b):                                                                                             
+    summed = a + b                                                                                          
+    print(summed)                                                                                      
+                                                                                                            
+if __name__ == "__main__":                                                                                  
+    sumab(5,3)