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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 recruit(self):
 """Recruit participants if necessary."""

        num_approved = len(Participant.query.filter_by(status="approved").all())
        end_of_generation = num_approved % self.generation_size == 0
        complete = num_approved >= (self.generations * self.generation_size)
        if complete:
            self.log("All networks full: closing recruitment", "-----")
            self.recruiter.close_recruitment()
        elif end_of_generation:
            self.log("generation finished, recruiting another")
            self.recruiter.recruit(n=self.generation_size)