def METHOD_NAME(event):
    if event.key == 'p':
        face_picking_filter.enabled = not face_picking_filter.enabled
        mesh.update_gl_state(blend=not face_picking_filter.enabled)
        mesh.update()
    if event.key == 'r':
        mesh.set_data(vertices, faces, face_colors=face_colors)
    if event.key == 's':
        shading_filter.shading = next(shading)
        mesh.update()
    if event.key == 'w':
        wireframe_filter.enabled = not wireframe_filter.enabled
        mesh.update()