code: def create_window(self, command=None, start_directory=None, name=None):
          
          assert command is None or isinstance(command, six.text_type)
          assert start_directory is None or isinstance(start_directory, six.text_type)
  
          pane = self._create_pane(None, command, start_directory=start_directory)
  
          self.arrangement.create_window(pane, name=name)
          pane.focus()
          self.invalidate()
docs: Create a new :class:`pymux.arrangement.Window` in the arrangement.