Erratum: use ar.result() in 5.3

Author: rossant

chapter5/53-parallel.ipynb

@@ -220,10 +220,10 @@
           "output_type": "execute_result"
         }
       ],
-      "source": "pi(np.sum(ar.result), n)"
+      "source": "pi(np.sum(ar.result()), n)"
     }
   ],
   "metadata": {},
   "nbformat": 4,
   "nbformat_minor": 0
-}
+}