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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fval(self, instance):
 """return the raw value that this property is holding internally for instance"""

        try:
            val = instance.__dict__[self.instance_field_name]
        except KeyError as e:
            #raise AttributeError(str(e))
            val = None

        return val