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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 asset_class(self) -> str: """ Returns the full asset class path for this stock """

        result = self.parent.name if self.parent else ""
        # Iterate to the top asset class and add names.
        cursor = self.parent
        while cursor:
            result = cursor.name + ":" + result
            cursor = cursor.parent
        return result