<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _tot_unhandled_services_by_state(self, state):
 """Generic function to get the number of unhandled problem services in the specified state :param state: state to filter on :type state: :return: number of service in state *state* and which are not acknowledged problems :rtype: int """

        return sum(1 for s in self.services if s.state == state and
                   s.is_problem and not s.problem_has_been_acknowledged)