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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 only_trashed(cls):
 """ Get a new query builder that only includes soft deletes :type cls: orator.orm.model.Model :rtype: orator.orm.builder.Builder """

        instance = cls()

        column = instance.get_qualified_deleted_at_column()

        return instance.new_query_without_scope(SoftDeletingScope()).where_not_null(
            column
        )