Update notebook

examples/workflow_by_code.ipynb

@@ -28,11 +28,17 @@
     "import sys, site\n",
     "from pathlib import Path\n",
     "\n",
+    "################################# NOTE #################################\n",
+    "#  Please be aware that if colab installs the latest numpy and pyqlib  #\n",
+    "#  in this cell, users should RESTART the runtime in order to run the  #\n",
+    "#  following cells successfully.                                       #\n",
+    "########################################################################\n",
     "\n",
     "try:\n",
     "    import qlib\n",
     "except ImportError:\n",
     "    # install qlib\n",
+    "    ! pip install --upgrade numpy\n",
     "    ! pip install pyqlib\n",
     "    # reload\n",
     "    site.main()\n",
@@ -238,9 +244,7 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "metadata": {
-    "scrolled": false
-   },
+   "metadata": {},
    "outputs": [],
    "source": [
     "from qlib.contrib.report import analysis_model, analysis_position\n",
@@ -359,7 +363,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.9"
+   "version": "3.8.3"
   },
   "toc": {
    "base_numbering": 1,
@@ -377,4 +381,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 4
-}
+}