Understanding `_` in Python

Understanding `_` in Python.ipynb

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    "> Namespaces are one honking great idea -- let's do more of those!\n",
    "— from \"The Zen of Python\"\n",
    "\n",
    "Namespaces keep things organized. \n",
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    "You don't want to add unnecessary variables to the namespace."
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      "hi\n",
      "hi\n",
      "hi\n",
      "hi\n",
      "hi\n"
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      "Variable   Type    Data/Info\n",
      "----------------------------\n",
      "i          int     4\n"
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    "`i` is in the namespace but is never used (and will never be used again)\n",
    "\n",
    "It is better to use a temporary variable that does not stay in the namespace."
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      "hi\n",
      "hi\n",
      "hi\n",
      "hi\n",
      "hi\n"
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    "for _ in range(5):\n",
    "    print('hi')"
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    "`_` is not in the namespace because it not needed."
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    " "
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