def get_next_duties_for_particular_student(self, student_id):
     q = DutyQuery()
     return q.get_next_duties_for_particular_student(student_id)
 def get_prev_duties(self):
     q = DutyQuery()
     return q.get_prev_duties()
 def get_next_duties(self):
     q = DutyQuery()
     return q.get_next_duties()
 def update_duty_by_id(self, duty):
     q = DutyQuery()
     return q.update_duty_by_id(duty)
 def delete_duty_by_id(self, duty_id):
     q = DutyQuery()
     return q.delete_duty_by_id(duty_id)
 def get_duties_by_s_id(self, student_id):
     q = DutyQuery()
     return q.get_duties_by_s_id(student_id)
 def get_duty_by_id(self, duty_id):
     q = DutyQuery()
     return q.get_duty_by_id(duty_id)
 def insert_duty(self, duty):
     q = DutyQuery()
     return q.insert_duty(duty)