Update method_overloading_extending_and_providing.py

Author: Quarkblue

Inheritance and Polymorphism/method_overloading_extending_and_providing.py

@@ -1,3 +1,51 @@
 # Method Overloading - Extending and Providing
 # Python beyond the basics - object oriented programming
 
+import abc
+
+class GetSetParent(metaclass = abc.ABCMeta):
+    
+    def __init__(self,value):
+        self.value = 0
+        
+    def set_val(self,value):
+        self.val = value
+        
+    def get_val(self):
+        return self.val
+    
+    @abc.abstractmethod
+    def showdoc(self):
+        return
+    
+    
+class GetSetInt(GetSetParent):
+    def set_val(self,value):
+        if not isinstance(value, int):
+            value = 0
+        """
+        if the value is not an integer then value is set as
+        the superclass/parent classes method "set_val" result
+        
+        "super(GetSetInt,self)" means the parent class of "GetSetInt"
+        """
+        super(GetSetInt, self).set_val(value)
+        
+    def showdoc(self):
+        print("GetSetInt object ({0}), only accepts integer values".format(id(self)))
+        
+class GetSetList(GetSetParent):
+    
+    def __init__(self,value=0):
+        self.vallist = [value]
+        
+    def get_val(self):
+        return self.vallist[-1]
+    def get_vals(self):
+        return self.vallist
+    
+    def set_val(self,value):
+        self.vallist.append(value)
+        
+    def showdoc(self):
+        print("GetSetList object, len{0}, stores history of values set".format(len(self.vallist)))