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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 validate_is_non_abstract_edge_type(self, edge_classname):
 """Validate that a edge classname corresponds to a non-abstract edge class."""

        element = self.get_edge_schema_element_or_raise(edge_classname)

        if element.abstract:
            raise InvalidClassError(u'Expected a non-abstract vertex class, but {} is abstract'
                                    .format(edge_classname))