07 - Exception handling.ipynb

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   "source": [
    "# Exception handling"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "with open('no-such-file.txt') as f:\n",
    "    print(f.read())"
   ]
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  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "*Note: Never ever do this!*"
   ]
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    "try:\n",
    "    # Some code\n",
    "except:\n",
    "    pass"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Handling multiple exceptions"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
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   "outputs": [],
   "source": [
    "try:\n",
    "    # Some code\n",
    "except FileNotFoundError as e:\n",
    "    handle_missing_file(e)\n",
    "except PermissionError as e:\n",
    "    handle_restricted_file(e)\n",
    "except:  # This is OK, since we raise it again below\n",
    "    general_filure_procedure(e)\n",
    "    raise  # Important! Don't silence when catching unknown exceptions!"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "`finally`. *Note: It doesn't even require an `except` block.*"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "try:\n",
    "    # Some code\n",
    "except SomeException as e:\n",
    "    print('SomeException happened: {}'.format(e))\n",
    "finally:\n",
    "    # This will be called regardless of success or failure"
   ]
  }
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