code: def extract(query_dict, prefix=""):
      
  
      strs = ['order_by']
      ints = ['per_page', 'page']
  
      extracted = { }
  
      for key in (strs + ints):
          if (prefix + key) in query_dict:
              val = query_dict.get(prefix + key)
  
              extracted[key] = (val
                  if not key in ints
                  else int(val))
  
      return extracted
docs: Extract the *order_by*, *per_page*, and *page* parameters from
      `query_dict` (a Django QueryDict), and return a dict suitable for
      instantiating a preconfigured Table object.