Update Day_12.md

Author: darkprinx

Status/Day_12.md

@@ -32,7 +32,8 @@ print (squaredNumbers)
 ***Define a class named American which has a static method called printNationality.***
 
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-### Hints: Use @staticmethod decorator to define class static method.
+### Hints: Use @staticmethod decorator to define class static method.There are also two more methods.To know more, go to this [link](https://realpython.com/blog/python/instance-class-and-static-methods-demystified/). 
+
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 **Main Author's Solution: Python 2**
 ```
@@ -48,6 +49,17 @@ American.printNationality()
 --------------------------
 **My Solution: Python 3**
 ```
+class American():
+ @staticmethod
+ def printNationality():
+ print("I am American")
+
+american = American()
+american.printNationality() # this will not run if @staticmethod does not decorates the function.
+ # Because the class has no inctance.
+
+American.printNationality() # this will run even though the @staticmethod
+ # does not decorate printNationality()
 ```
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