code: def get_load_time(self, request_type=None, content_type=None,
                        status_code=None, asynchronous=True, **kwargs):
          
          entries = self.filter_entries(
              request_type=request_type, content_type=content_type,
              status_code=status_code
          )
  
          if "async" in kwargs:
              asynchronous = kwargs['async']
  
          if not asynchronous:
              time = 0
              for entry in entries:
                  time += entry['time']
              return time
          else:
              return len(self.parser.create_asset_timeline(entries))
docs: This method can return the TOTAL load time for the assets or the ACTUAL
          load time, the difference being that the actual load time takes
          asynchronous transactions into account. So, if you want the total load
          time, set asynchronous=False.
  
          EXAMPLE:
  
          I want to know the load time for images on a page that has two images,
          each of which took 2 seconds to download, but the browser downloaded
          them at the same time.
  
          self.get_load_time(content_types=['image']) (returns 2)
          self.get_load_time(content_types=['image'], asynchronous=False) (returns 4)