I have a model
class Booked(models.Model):
    start_date_time = models.DateTimeField()
    end_date_time = models.DateTimeField()
    resource = models.ForeignKey(Resouce)
How do I check if a particular datetime range doesn't fall between the start or end datetimes of any of the booked objects?
I want to check if I can book a resource with say book_start_date and book_end_date without it being already booked during that range 
 
     
    