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   "source": [
    "### <center>San Jose State University<br>Department of Applied Data Science<br><br>**DATA 200<br>Computational Programming for Data Analytics**<br><br>Spring 2024<br>Instructor: Ron Mak</center>"
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    "# Autogenerated Classes"
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   "source": [
    "#### Recall the class `Card` in source file `card.py` from a few weeks ago."
   ]
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   "source": [
    "#### We can use Python's **autogeneration** feature to automatically generate boilerplate code that's common in most classes."
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    "#### We need to import `dataclass` from the built-in `dataclasses` module, and `ClassVar` and `List` from the build-in `typing` module. See source file `carddataclass.py`.\n",
    "```\n",
    "from dataclasses import dataclass\n",
    "from typing import ClassVar, List\n",
    "```"
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    "#### The `@dataclass` decorator indicates a data class. A data class declare both class attributes and data attributes inside the class but outside the class methods. Data classes require additional information (*hints*) to distinguish class attributes from data attributes. These hints affect how the autogenerated methods are implemented.\n",
    "```\n",
    "@dataclass\n",
    "class Card:\n",
    "    FACES: ClassVar[List[str]] = ['Ace', '2', '3', '4', '5', '6', '7', \n",
    "                                  '8', '9', '10', 'Jack', 'Queen', 'King']\n",
    "    SUITS: ClassVar[List[str]] = ['Hearts', 'Diamonds', 'Clubs', 'Spades']\n",
    "\n",
    "    face: str\n",
    "    suit: str\n",
    "```"
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   "source": [
    "#### In the above, the **variable annotation** `ClassVar[List[str]]` is a type hint that specifies `FACES` and `SUITS` are class variables that refer to lists of strings. On the other hand, `face` and `suit` are data attributes that belong to each instantiated object."
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