Vwp/docs improved document loaders (#4006)

Huge thanks to @leo-gan for improving the document loaders notebooks

---------

Co-authored-by: Leonid Ganeline <leo.gan.57@gmail.com>

docs/modules/indexes/document_loaders/examples/hn.ipynb

@@ -6,14 +6,19 @@
    "metadata": {},
    "source": [
     "# Hacker News\n",
-    "How to pull page data and comments from Hacker News"
+    "\n",
+    ">[Hacker News](https://en.wikipedia.org/wiki/Hacker_News) (sometimes abbreviated as HN) is a social news website focusing on computer science and entrepreneurship. It is run by the investment fund and startup incubator Y Combinator. In general, content that can be submitted is defined as \"anything that gratifies one's intellectual curiosity.\"\n",
+    "\n",
+    "This notebook covers how to pull page data and comments from [Hacker News](https://news.ycombinator.com/)"
    ]
   },
   {
    "cell_type": "code",
    "execution_count": 1,
    "id": "ff49b177",
-   "metadata": {},
+   "metadata": {
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "from langchain.document_loaders import HNLoader"
@@ -23,7 +28,9 @@
    "cell_type": "code",
    "execution_count": 2,
    "id": "849a8d52",
-   "metadata": {},
+   "metadata": {
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "loader = HNLoader(\"https://news.ycombinator.com/item?id=34817881\")"
@@ -33,7 +40,9 @@
    "cell_type": "code",
    "execution_count": 3,
    "id": "c2826836",
-   "metadata": {},
+   "metadata": {
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "data = loader.load()"
@@ -43,15 +52,14 @@
    "cell_type": "code",
    "execution_count": 4,
    "id": "fefa2adc",
-   "metadata": {},
+   "metadata": {
+    "tags": []
+   },
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "[Document(page_content=\"delta_p_delta_x 18 hours ago  \\n             | next [–] \\n\\nAstrophysical and cosmological simulations are often insightful. They're also very cross-disciplinary; besides the obvious astrophysics, there's networking and sysadmin, parallel computing and algorithm theory (so that the simulation programs are actually fast but still accurate), systems design, and even a bit of graphic design for the visualisations.Some of my favourite simulation projects:- IllustrisTNG: https://www.tng-project.org/- SWIFT: https://swift.dur.ac.uk/- CO5BOLD: https://www.astro.uu.se/~bf/co5bold_main.html (which produced these animations of a red-giant star: https://www.astro.uu.se/~bf/movie/AGBmovie.html)- AbacusSummit: https://abacussummit.readthedocs.io/en/latest/And I can add the simulations in the article, too.\\n \\nreply\", lookup_str='', metadata={'source': 'https://news.ycombinator.com/item?id=34817881', 'title': 'What Lights the Universe’s Standard Candles?'}, lookup_index=0),\n",
-       " Document(page_content=\"andrewflnr 19 hours ago  \\n             | prev | next [–] \\n\\nWhoa. I didn't know the accretion theory of Ia supernovae was dead, much less that it had been since 2011.\\n \\nreply\", lookup_str='', metadata={'source': 'https://news.ycombinator.com/item?id=34817881', 'title': 'What Lights the Universe’s Standard Candles?'}, lookup_index=0),\n",
-       " Document(page_content='andreareina 18 hours ago  \\n             | prev | next [–] \\n\\nThis seems  to be the paper https://academic.oup.com/mnras/article/517/4/5260/6779709\\n \\nreply', lookup_str='', metadata={'source': 'https://news.ycombinator.com/item?id=34817881', 'title': 'What Lights the Universe’s Standard Candles?'}, lookup_index=0),\n",
-       " Document(page_content=\"andreareina 18 hours ago  \\n             | prev [–] \\n\\nWouldn't double detonation show up as variance in the brightness?\\n \\nreply\", lookup_str='', metadata={'source': 'https://news.ycombinator.com/item?id=34817881', 'title': 'What Lights the Universe’s Standard Candles?'}, lookup_index=0)]"
+       "\"delta_p_delta_x 73 days ago  \\n             | next [–] \\n\\nAstrophysical and cosmological simulations are often insightful. They're also very cross-disciplinary; besides the obvious astrophysics, there's networking and sysadmin, parallel computing and algorithm theory (so that the simulation programs a\""
       ]
      },
      "execution_count": 4,
@@ -60,16 +68,32 @@
     }
    ],
    "source": [
-    "data"
+    "data[0].page_content[:300]"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 5,
    "id": "938ff4ee",
-   "metadata": {},
-   "outputs": [],
-   "source": []
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "{'source': 'https://news.ycombinator.com/item?id=34817881',\n",
+       " 'title': 'What Lights the Universe’s Standard Candles?'}"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "data[0].metadata"
+   ]
   }
  ],
  "metadata": {
@@ -88,7 +112,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.1"
+   "version": "3.10.6"
   },
   "vscode": {
    "interpreter": {