revert URLs to internal files

Author: rlanzafame

book/06/Exercises/01.ipynb

@@ -142,7 +142,7 @@
     "import numpy as np\n",
     "import pandas as pd\n",
     "\n",
-    "file_location = (\"https://raw.githubusercontent.com/TUDelft-books/learn-pythonhon/main/book/06/Theory/\")\n",
+    "file_location = (\"https://raw.githubusercontent.com/teachbooks/learn-pythonhon/main/book/06/Theory/\")\n",
     "mineral_properties = pd.read_csv(file_location + 'mineral_properties.txt', \n",
     "                  skiprows=1,skipinitialspace=True)\n",
     "mineral_properties['new_column'] = np.nan\n",
@@ -284,7 +284,7 @@
    },
    "outputs": [],
    "source": [
-    "file_location = (\"https://raw.githubusercontent.com/TUDelft-books/learn-pythonhonhon/main/book/06/Exercises/\")\n",
+    "file_location = (\"https://raw.githubusercontent.com/teachbooks/learn-pythonhonhon/main/book/06/Exercises/\")\n",
     "\n",
     "mountains_8000 = ... #1 \n",
     "cols = ... #2 \n",
@@ -359,7 +359,7 @@
    },
    "outputs": [],
    "source": [
-    "file_location = (\"https://raw.githubusercontent.com/TUDelft-books/learn-pythonhon/main/book/06/Exercises/\")\n",
+    "file_location = (\"https://raw.githubusercontent.com/teachbooks/learn-pythonhon/main/book/06/Exercises/\")\n",
     "\n",
     "mountains_7000 = ... # 1\n",
     "df_concat = ... # 2\n",