{
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  {
   "cell_type": "markdown",
   "id": "b0a67390",
   "metadata": {},
   "source": [
    "# Pickle-Beispiele"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "1e3f1486",
   "metadata": {},
   "source": [
    "## Python-`pickle`-Modul\n",
    "\n",
    "In diesem Beispiel wollen wir mit dem Python [pickle](https://docs.python.org/3/library/pickle.html)-Modul das foldende Dict im Pickle-Format speichern:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "id": "4df6709f",
   "metadata": {
    "execution": {
     "iopub.execute_input": "2026-05-22T08:26:06.583159Z",
     "iopub.status.busy": "2026-05-22T08:26:06.582745Z",
     "iopub.status.idle": "2026-05-22T08:26:06.586455Z",
     "shell.execute_reply": "2026-05-22T08:26:06.585916Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.583140Z"
    }
   },
   "outputs": [],
   "source": [
    "pyviz = {\n",
    "    \"Titel\": \"PyViz Tutorial\",\n",
    "    \"Sprache\": \"de\",\n",
    "    \"Autor*innen\": \"Veit Schiele\",\n",
    "    \"Lizenz\": \"BSD-3-Clause\",\n",
    "    \"Veröffentlichungsdatum\": \"2020-04-13\",\n",
    "}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "a1b0ed14",
   "metadata": {
    "execution": {
     "iopub.execute_input": "2026-05-22T08:26:06.587130Z",
     "iopub.status.busy": "2026-05-22T08:26:06.586985Z",
     "iopub.status.idle": "2026-05-22T08:26:06.589364Z",
     "shell.execute_reply": "2026-05-22T08:26:06.588905Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.587115Z"
    }
   },
   "outputs": [],
   "source": [
    "import pickle\n",
    "\n",
    "from pathlib import Path"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "2504a8a1",
   "metadata": {
    "execution": {
     "iopub.execute_input": "2026-05-22T08:26:06.590061Z",
     "iopub.status.busy": "2026-05-22T08:26:06.589909Z",
     "iopub.status.idle": "2026-05-22T08:26:06.593095Z",
     "shell.execute_reply": "2026-05-22T08:26:06.592772Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.590038Z"
    }
   },
   "outputs": [],
   "source": [
    "with Path.open(\"pyviz.pkl\", \"wb\") as f:\n",
    "    pickle.dump(pyviz, f, pickle.HIGHEST_PROTOCOL)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "678c6444",
   "metadata": {},
   "source": [
    "Nun lesen wir die Pickle-Datei wieder ein:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "id": "209a46ed",
   "metadata": {
    "execution": {
     "iopub.execute_input": "2026-05-22T08:26:06.593746Z",
     "iopub.status.busy": "2026-05-22T08:26:06.593643Z",
     "iopub.status.idle": "2026-05-22T08:26:06.596732Z",
     "shell.execute_reply": "2026-05-22T08:26:06.595911Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.593736Z"
    }
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'Titel': 'PyViz Tutorial', 'Sprache': 'de', 'Autor*innen': 'Veit Schiele', 'Lizenz': 'BSD-3-Clause', 'Veröffentlichungsdatum': '2020-04-13'}\n"
     ]
    }
   ],
   "source": [
    "with Path.open(\"pyviz.pkl\", \"rb\") as f:\n",
    "    pyviz = pickle.load(f)\n",
    "\n",
    "print(pyviz)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "02b84446",
   "metadata": {},
   "source": [
    "Auf diese Weise können wir Python-Objekte einfach persistent speichern.\n",
    "\n",
    "<div class=\"alert alert-block alert-warning\">\n",
    "\n",
    "**Warnung**\n",
    "\n",
    "`pickle` kann nur als kurzfristiges Speicherformat empfohlen werden. Das Problem ist, dass nicht garantiert wird, dass das Format im Laufe der Zeit stabil bleibt; ein heute gepickeltes Objekt lässt sich möglicherweise mit einer späteren Version der Bibliothek nicht mehr entpickeln.\n",
    "</div>\n",
    "<div class=\"alert alert-block alert-warning\">\n",
    "\n",
    "**Warnung**\n",
    "\n",
    "`pickle` und Module, die darauf aufbauen, können bei der Deserialisierung nicht vertrauenswürdiger Daten Sicherheitsrisiken bergen.\n",
    "</div>"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "492079d2",
   "metadata": {},
   "source": [
    "## pandas\n",
    "\n",
    "Alle Pandas-Objekte haben eine `to_pickle`-Methode, die Daten im Pickle-Format auf die Festplatte schreibt:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "id": "3e8c1438",
   "metadata": {
    "execution": {
     "iopub.execute_input": "2026-05-22T08:26:06.597450Z",
     "iopub.status.busy": "2026-05-22T08:26:06.597362Z",
     "iopub.status.idle": "2026-05-22T08:26:06.815452Z",
     "shell.execute_reply": "2026-05-22T08:26:06.815120Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.597440Z"
    }
   },
   "outputs": [
    {
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       "<style scoped>\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>Titel</th>\n",
       "      <th>Sprache</th>\n",
       "      <th>Autor*innen</th>\n",
       "      <th>Lizenz</th>\n",
       "      <th>Veröffentlichungsdatum</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Python basics</td>\n",
       "      <td>en</td>\n",
       "      <td>Veit Schiele</td>\n",
       "      <td>BSD-3-Clause</td>\n",
       "      <td>2021-10-28</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Jupyter Tutorial</td>\n",
       "      <td>en</td>\n",
       "      <td>Veit Schiele</td>\n",
       "      <td>BSD-3-Clause</td>\n",
       "      <td>2019-06-27</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jupyter Tutorial</td>\n",
       "      <td>de</td>\n",
       "      <td>Veit Schiele</td>\n",
       "      <td>BSD-3-Clause</td>\n",
       "      <td>2020-10-26</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>PyViz Tutorial</td>\n",
       "      <td>en</td>\n",
       "      <td>Veit Schiele</td>\n",
       "      <td>BSD-3-Clause</td>\n",
       "      <td>2020-04-13</td>\n",
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      "text/plain": [
       "              Titel Sprache   Autor*innen        Lizenz Veröffentlichungsdatum\n",
       "0     Python basics      en  Veit Schiele  BSD-3-Clause             2021-10-28\n",
       "1  Jupyter Tutorial      en  Veit Schiele  BSD-3-Clause             2019-06-27\n",
       "2  Jupyter Tutorial      de  Veit Schiele  BSD-3-Clause             2020-10-26\n",
       "3    PyViz Tutorial      en  Veit Schiele  BSD-3-Clause             2020-04-13"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "\n",
    "books = pd.read_pickle(\"books.pkl\")\n",
    "\n",
    "books"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "65d0c640",
   "metadata": {},
   "source": [
    "pandas-Objekte haben alle eine `to_pickle`-Methode, die die Daten im Pickle-Format auf die Festplatte schreibt:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "id": "cb529da7",
   "metadata": {
    "execution": {
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     "iopub.status.idle": "2026-05-22T08:26:06.819747Z",
     "shell.execute_reply": "2026-05-22T08:26:06.819506Z",
     "shell.execute_reply.started": "2026-05-22T08:26:06.817588Z"
    }
   },
   "outputs": [],
   "source": [
    "books.to_pickle(\"books.pkl\")"
   ]
  }
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