def update_passenger_fare(service_no, sector_id, fare_type):
s = db.Key.from_path('Sector', sector_id)
p = db.Key.from_path('Passenger', service_no)
psb = PassengerSectorBooking.get_by_key_name(str(p)+str(s))
res = None
if psb:
psb.fare_type = fare_type
psb.put()
_use(psb.booking.key())
_use(psb.passenger.key())
res = psb.passenger.to_dict()
res['fare'] = fare_type
return res
