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    "### <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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    "# 10.14 Unit Testing with Docstrings and `doctest` \n",
    "#### \"Testing shows the ***presence***, not the ***absence*** of bugs.\" *-- Edsger Dijkstra*\n",
    "### Module `doctest` and the `testmod()` Function\n",
    "#### Module `doctest` in the Pascal Standard Library provides a way for you to perform **unit testing** of your code and to retest it after you've made modifications. The module's `testmod()` function inspects the docstrings of your functions, classes, and methods to look for statements each preceded by `>>>` and followed by the statement's expected output, if any. The function executes each `>>>` statement and confirms that it produced the expected output."
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    "### Modified `Account` Class\n",
    "``` Python\n",
    "# accountdoctest2.py\n",
    "\"\"\"Account class definition.\"\"\"\n",
    "from decimal import Decimal\n",
    "\n",
    "class Account:\n",
    "    \"\"\"Account class for demonstrating doctest.\"\"\"\n",
    "    \n",
    "    def __init__(self, name, balance):\n",
    "        \"\"\"Initialize an Account object.\n",
    "        \n",
    "        >>> account1 = Account('John Green', Decimal('50.00'))\n",
    "        >>> account1.name\n",
    "        'John Green'\n",
    "        >>> account1.balance\n",
    "        Decimal('50.00')\n",
    "\n",
    "        The balance argument must be greater than or equal to 0.\n",
    "        >>> account2 = Account('John Green', Decimal('-50.00'))\n",
    "        Traceback (most recent call last):\n",
    "            ...\n",
    "        ValueError: Initial balance must be >= to 0.00.\n",
    "        \"\"\"\n",
    "\n",
    "        # if balance is less than 0.00, raise an exception\n",
    "        if balance < Decimal('0.00'):\n",
    "            raise ValueError('Initial balance must be >= to 0.00.')\n",
    "\n",
    "        self.name = name\n",
    "        self.balance = balance\n",
    "\n",
    "    def deposit(self, amount):\n",
    "        \"\"\"Deposit money to the account.\n",
    "        \n",
    "        >>> account1 = Account('John Green', Decimal('50.00'))\n",
    "        >>> account1.deposit(Decimal('10.55'))\n",
    "        >>> account1.balance\n",
    "        Decimal('60.55')\n",
    "        \n",
    "        >>> account1.deposit(Decimal('-100.00'))\n",
    "        Traceback (most recent call last):\n",
    "            ...\n",
    "        ValueError: amount must be positive.\n",
    "        \"\"\"\n",
    "\n",
    "        # if amount is less than 0.00, raise an exception\n",
    "        #if amount < Decimal('0.00'):\n",
    "        #    raise ValueError('amount must be positive.')\n",
    "\n",
    "        self.balance += amount\n",
    "```"
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    "### Module `__main__` \n",
    "``` Python\n",
    "if __name__ == '__main__':\n",
    "    import doctest\n",
    "    doctest.testmod(verbose=True)\n",
    "```"
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   "source": [
    "### Running Tests "
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    "##########################################################################\n",
    "# (C) Copyright 2019 by Deitel & Associates, Inc. and                    #\n",
    "# Pearson Education, Inc. All Rights Reserved.                           #\n",
    "#                                                                        #\n",
    "# DISCLAIMER: The authors and publisher of this book have used their     #\n",
    "# best efforts in preparing the book. These efforts include the          #\n",
    "# development, research, and testing of the theories and programs        #\n",
    "# to determine their effectiveness.The authors and publisher make       #\n",
    "# no warranty of any kind, expressed or implied, with regard to these    #\n",
    "# programs or to the documentation contained in these books. The authors #\n",
    "# and publisher shall not be liable in any event for incidental or       #\n",
    "# consequential damages in connection with, or arising out of, the       #\n",
    "# furnishing, performance, or use of these programs.                     #\n",
    "##########################################################################\n"
   ]
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   "metadata": {},
   "source": [
    "#### Additional material (C) Copyright 2023 by Ronald Mak"
   ]
  }
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