@property
    def viewers(self):
        result = []
        for t in range(self.tab_count):
            tab = self.tab(t)
            item = []
            for subwindow in tab.subWindowList():
                widget = subwindow.widget()
                if isinstance(widget, DataViewer):
                    item.append(widget)
            result.append(tuple(item))
        return tuple(result)
A list of lists of open Data Viewers.
dataset/ETHPy150Open glue-viz/glue/glue/app/qt/application.py/GlueApplication.viewers