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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 add_class_properties_xsd(self, tb, cls):
 """ Add the XSD for the class properties to the ``TreeBuilder``. And call the user ``sequence_callback``. """

        for p in class_mapper(cls).iterate_properties:
            if isinstance(p, ColumnProperty):
                self.add_column_property_xsd(tb, p)
        if self.sequence_callback:
            self.sequence_callback(tb, cls)