ERROR
If you get the error you're encountering, unsupported operand type(s) for -: 'float' and 'NoneType', is happening in the count_available method of your Schedule model, specifically in your models.py file, at line 57.
\btrs_django\reservationApp\models.py
in code line 57
def count_available(self):
booked = Booking.objects.filter(schedule=self).aggregate(Sum('seats'))['seats__sum']
return self.bus.seats - booked
chage this to
def count_available(self):
booked = Booking.objects.filter(schedule=self).aggregate(Sum('seats'))['seats__sum']
# Check if booked is None, and if so, set it to 0
if booked is None:
booked = 0
return self.bus.seats - booked
