code: def _create_select_window_handler(self, window):
          " Return a mouse handler that selects the given window when clicking. "
          def handler(mouse_event):
              if mouse_event.event_type == MouseEventType.MOUSE_DOWN:
                  self.pymux.arrangement.set_active_window(window)
                  self.pymux.invalidate()
              else:
                  return NotImplemented  # Event not handled here.
          return handlef _create_select_window_handler(self, window):
          " Return a mouse handler that selects the given window when clicking. "
          def handler(mouse_event):
              if mouse_event.event_type == MouseEventType.MOUSE_DOWN:
                  self.pymux.arrangement.set_active_window(window)
                  self.pymux.invalidate()
              else:
                  return NotImplemented  # Event not handled here.
          return handler
docs: Return a mouse handler that selects the given window when clicking.