python/Context Managers.ipynb

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   "source": [
    "## Taking care of two resources simultaneously\n",
    "\n",
    "import sqlite3\n",
    "import tempfile\n",
    "import contextlib\n",
    "from os.path import isfile"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "@contextlib.contextmanager\n",
    "def create_temp_db():\n",
    "    with tempfile.NamedTemporaryFile() as temp_db:\n",
    "        with sqlite3.connect(temp_db.name) as conn:\n",
    "            yield (temp_db, conn)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "/tmp/tmpxgu8wuij\n",
      "True\n",
      "<sqlite3.Connection object at 0x7f8ba57b2570>\n"
     ]
    }
   ],
   "source": [
    "with create_temp_db() as (db_file, db_conn):\n",
    "    print(db_file.name)\n",
    "    print(isfile(db_file.name))\n",
    "    print(db_conn)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n"
     ]
    }
   ],
   "source": [
    "print(isfile(db_file.name))"
   ]
  }
 ],
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