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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 delete(self, constraint):
 """ Delete a record from the repository """


        results = self._get_repo_filter(Service.objects).extra(where=[constraint['where']],
                                                               params=constraint['values']).all()
        deleted = len(results)
        results.delete()
        return deleted