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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 _get_total_services_problems_handled(self):
 """ Get the number of service problems not handled :return: Number of services which are problems and not handled :rtype: int """

        return sum(1 for s in self.services if s.is_problem and s.problem_has_been_acknowledged)