enhance Broccoli.ipynb

Author: Wei1234c

notebooks/demo/Broccoli_readme_en.ipynb

@@ -44,7 +44,8 @@
     "### Implemented Canvas functionalities:\n",
     "\n",
     "- **[Chains](http://docs.celeryproject.org/en/latest/userguide/canvas.html#chains)** The main purpose is to cascade multiple operations, The result of previous operation is the parameter of the next operation. For example, the following example uses `chain` to perform ((4+4) * 8) * 10 = 640  \n",
-    "   \n",
+    "\n",
+    "\n",
     "```\n",
     ">>> # (4 + 4) * 8 * 10\n",
     ">>> res = chain(add.s(4, 4), mul.s(8), mul.s(10))\n",
@@ -55,7 +56,7 @@
     "640\n",
     "```\n",
     "\n",
-    "- **[Groups](http://docs.celeryproject.org/en/latest/userguide/canvas.html#groups)** main purpose is to parallel multiple operations, sending multiple homogeneity tasks to many remote workers for processing, and then collect results returned by the workers, combine them into a set of results. For example, the following example uses `group` to calculate (2+2) and (4+4) simultaneously. The result is [4, 8]\n",
+    "- **[Groups](http://docs.celeryproject.org/en/latest/userguide/canvas.html#groups)** main purpose is to parallel multiple operations, sending multiple homogeneity tasks to many remote workers for processing, and then collect results returned by the workers, combine them into a set of results. For example, the following example uses `group` to calculate (2+2) and (4+4) simultaneously. The result is [4, 8]  \n",
     "\n",
     "```\n",
     ">>> group(add.s(2, 2), add.s(4, 4))\n",