title: datetime excluding weekend in django
body: <p>I have an problem regarding my datetime,I need a date excluding weekend for last 15 days,I am solving this issue but I got all the date including weekends.
  Here is my code:-</p>
  
  <pre><code>days_to_show = 15
      start_date = datetime.date.today() - datetime.timedelta(days=days_to_show)
      #print start_date
      query = Book.objects.values('startdate').order_by('timeid') \
             .annotate(spent=Sum('spent')) \
             .filter(project_id=project_id,
                     startdate__range=(start_date, datetime.datetime.now()))
  
      spent_dict = dict((d['startdate'], d['spent']) for d in query)
      date_list = [str((start_date) + (datetime.timedelta(days=day)))
                               for day in range(0, days_to_show)]
  
  
      sp_data['time'] = [{'startdate': date, "spent":spent_dict.get(str(date),0)}
                               for date in date_list ]
  </code></pre>