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{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Pickle"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {},
"outputs": [],
"source": [
"import pickle\n",
"class StudentObject:\n",
" def __init__(self):\n",
" "
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Using `pickle` to write multiple records\n",
"- input a student record and save it to a new serial file\n",
"- read a student record from that file\n",
"- extend your program to work for more than one record"
]
},
{
"cell_type": "code",
"execution_count": 20,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"John born on 2025-03-04 15:15:35.959676, full time is yes\n",
"John born on 2025-03-04 15:14:04.842286, full time is yes\n",
"Jake born on 2025-03-04 15:14:04.842378, full time is yes\n"
]
}
],
"source": [
"import datetime\n",
"import pickle\n",
"DATA_FILENAME = \"student_data.dat\"\n",
"class Student:\n",
" def __init__(self, name, dob):\n",
" self.__Name = name\n",
" self.__DateOfBirth = dob\n",
" self.__FullTime = True\n",
" def GetName(self):\n",
" return self.__Name\n",
" def __str__(self):\n",
" return f\"{self.__Name} born on {self.__DateOfBirth}, full time is {'yes' if self.__FullTime else 'nah'}\"\n",
"def write_to_file(obj):\n",
" with open(DATA_FILENAME, 'ab+') as file:\n",
" pickle.dump(obj, file)\n",
" file.close()\n",
"def read_from_file():\n",
" with open(DATA_FILENAME, 'rb') as file:\n",
" s1 = pickle.load(file)\n",
" s2 = pickle.load(file)\n",
" file.close()\n",
" print(s1)\n",
" print(s2)\n",
"s1 = Student(\"John\", datetime.datetime.now())\n",
"s2 = Student(\"Jake\", datetime.datetime.now())\n",
"s3 = Student(\"Jaguar\", datetime.datetime.now())\n",
"s4 = Student(\"Jack\", datetime.datetime.now())\n",
"s5 = Student(\"Jacqueline\", datetime.datetime.now())\n",
"s6 = Student(\"Jiashuo\", datetime.datetime.now())\n",
"print(s1)\n",
"write_to_file(s1)\n",
"write_to_file(s2)\n",
"write_to_file(s3)\n",
"read_from_file()\n"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Activity 20M, with pickles"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {},
"outputs": [],
"source": []
}
],
"metadata": {
"kernelspec": {
"display_name": "Python 3",
"language": "python",
"name": "python3"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.12.7"
}
},
"nbformat": 4,
"nbformat_minor": 2
}
|
