def worldTooltipText(self):
        """
        Displays the corresponding tooltip if ALT is pressed.
        Called by leveleditor every tick.
        """
        if self.pickBlockKey:
            try:
                if self.editor.blockFaceUnderCursor is None:
                    return
                pos = self.editor.blockFaceUnderCursor[0]
                blockID = self.editor.level.blockAt(*pos)
                blockdata = self.editor.level.blockDataAt(*pos)
                return _("Click to use {0} ({1}:{2})").format(self.editor.level.materials.names[blockID][blockdata], blockID, blockdata)
            except Exception as e:
                return repr(e)

        Displays the corresponding tooltip if ALT is pressed.
        Called by leveleditor every tick.
        
editortools/brush.py