Reset graph data and display empty graph

def on_reset_button(self, _):
        """Reset graph data and display empty graph"""
        for graph in self.visible_graphs.values():
            graph.reset()
        for graph in self.graphs.values():
            try:
                graph.source.reset()
            except NotImplementedError:
                pass
        # Reset clock
        self.clock_view.set_text(ZERO_TIME)

        self.update_displayed_information()