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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 top_class(self):
 """reference to a parent class, which contains this class and defined within a namespace if this class is defined under a namespace, self will be returned"""

        curr = self
        parent = self.parent
        while isinstance(parent, class_t):
            curr = parent
            parent = parent.parent
        return curr