add brackets to satisfy the new sequence requirement

Author: v0lta

galleries/examples/animation/frame_grabbing_sgskip.py

@@ -39,5 +39,5 @@
     for i in range(100):
         x0 += 0.1 * np.random.randn()
         y0 += 0.1 * np.random.randn()
-        l.set_data(x0, y0)
+        l.set_data([x0], [y0])
         writer.grab_frame()