increment 30 minutes in time in loop append in list in django

Need to add the time in list from starting time and ending time given

   timing =  timings.objects.all()

      monday_time = timing.monday_time
      teusday_time = timing.teuday_time
      ...

   x = monday_time + datetime.time('00:30')

This is not working , this give the error of typeError, How to increment time and add on list.