from containers.models import Container

def get_container_for_booking(booking):
    filters = {
        'expedited': False,
    }

    if booking.container_number:
        filters['container_number'] = booking.container_number
    else:
        filters['container_type'] = booking.container_type
        filters['line'] = booking.line

    return Container.objects.filter(**filters).order_by('created_at').first()