Merge pull request #498 from Masood-Akram/fix/notebook-fix

colab: make setup cell more robust

Author: zivy

Python/01_Image_Basics.ipynb

@@ -23,12 +23,19 @@
    "outputs": [],
    "source": [
     "# Setup to enable running the notebook in the Google Colab environment\n",
-    "import os\n",
     "\n",
-    "if \"COLAB_NOTEBOOK_ID\" in os.environ:\n",
-    "    !git clone https://github.com/InsightSoftwareConsortium/SimpleITK-Notebooks\n",
+    "try:\n",
+    "    import google.colab\n",
+    "    import pathlib\n",
+    "\n",
+    "    repo_dir = pathlib.Path(\"SimpleITK-Notebooks\")\n",
+    "    if not repo_dir.exists():\n",
+    "        !git clone --depth 1 https://github.com/InsightSoftwareConsortium/SimpleITK-Notebooks\n",
     "    %cd SimpleITK-Notebooks/Python\n",
-    "    !pip install -q -r requirements.txt"
+    "    !pip install -q -r requirements.txt\n",
+    "\n",
+    "except ImportError:\n",
+    "    pass  # not on Colab"
    ]
   },
   {

Python/36_Microscopy_Colocalization_Distance_Analysis.ipynb

@@ -25,7 +25,6 @@
     "import numpy as np\n",
     "import pandas as pd\n",
     "\n",
-    "\n",
     "%matplotlib widget\n",
     "import gui\n",
     "\n",

Python/71_Trust_But_Verify.ipynb

@@ -75,7 +75,6 @@
     "import matplotlib.pyplot as plt\n",
     "import ipywidgets as widgets\n",
     "\n",
-    "\n",
     "# utility method that either downloads data from the Girder repository or\n",
     "# if already downloaded returns the file name for reading from disk (cached data)\n",
     "%run update_path_to_download_script\n",