update File IO

demos/users.yaml

@@ -1,3 +1,4 @@
+# list of players information
 - email: [email protected]
   lost: 2
   name: John Doe

notebooks/Ch10-1-Files.ipynb

@@ -1822,32 +1822,31 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 16,
+   "execution_count": 32,
    "metadata": {},
    "outputs": [],
    "source": [
     "def get_hashed_password(password, salt):\n",
     "    import hashlib\n",
-    "    return hashlib.sha256((password + salt).encode('utf-8')).hexdigest()"
+    "    round = 100_000\n",
+    "    return hashlib.pbkdf2_hmac('sha256', password.encode('utf-8'), salt.encode('utf-8'), round).hex().upper()"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 17,
+   "execution_count": null,
    "metadata": {},
    "outputs": [
     {
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "salt = 'PJLLqVpW4qpa1hIu'\n",
-      "hashed_password = 'bc0951eff5171243056cd7a3a073ba8b2366a8230c997c5fac8cd3052d20fcec'\n"
+      "salt = 'MPWAcxbAyiVXdpeU'\n",
+      "hashed_password = 'AFE4AD9E6FF039DCD90C82705C94AC3EB231AB6B8045D2B1B519640DA8518B22'\n"
      ]
     }
    ],
    "source": [
-    "import hashlib\n",
-    "\n",
     "salt = get_random_salt()\n",
     "print(f'{salt = }')\n",
     "salted_password = 'P@ssw0rd'+salt\n",
@@ -1857,49 +1856,31 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 34,
    "metadata": {},
    "outputs": [],
    "source": [
     "# create a new player\n",
     "new_user = {}\n",
-    "new_user['name']= 'Michael Jordan'\n",
-    "new_user['email']= '[email protected]'\n",
-    "new_user['password']= hashed_password\n",
-    "new_user['salt']= salt\n",
+    "new_user['name'] = 'Michael Jordan'\n",
+    "new_user['email'] = '[email protected]'\n",
+    "new_user['password'] = hashed_password\n",
+    "new_user['salt'] = salt\n",
     "new_user['played'] = 20\n",
     "new_user['lost'] = 5"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 35,
    "metadata": {},
    "outputs": [
     {
-     "data": {
-      "text/plain": [
-       "[{'name': 'John Doe',\n",
-       "  'email': '[email protected]',\n",
-       "  'password': 'password',\n",
-       "  'played': 10,\n",
-       "  'lost': 2},\n",
-       " {'name': 'Jane Doe',\n",
-       "  'email': '[email protected]',\n",
-       "  'password': 'password123',\n",
-       "  'played': 5,\n",
-       "  'lost': 1},\n",
-       " {'name': 'Michael Jordan',\n",
-       "  'email': '[email protected]',\n",
-       "  'password': 'bc0951eff5171243056cd7a3a073ba8b2366a8230c997c5fac8cd3052d20fcec',\n",
-       "  'salt': 'PJLLqVpW4qpa1hIu',\n",
-       "  'played': 20,\n",
-       "  'lost': 5}]"
-      ]
-     },
-     "execution_count": 23,
-     "metadata": {},
-     "output_type": "execute_result"
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "[{'name': 'John Doe', 'email': '[email protected]', 'password': 'password', 'played': 10, 'lost': 2}, {'name': 'Jane Doe', 'email': '[email protected]', 'password': 'password123', 'played': 5, 'lost': 1}, {'name': 'Michael Jordan', 'email': '[email protected]', 'password': 'bc0951eff5171243056cd7a3a073ba8b2366a8230c997c5fac8cd3052d20fcec', 'salt': 'PJLLqVpW4qpa1hIu', 'played': 20, 'lost': 5}, {'name': 'Michael Jordan', 'email': '[email protected]', 'password': 'AFE4AD9E6FF039DCD90C82705C94AC3EB231AB6B8045D2B1B519640DA8518B22', 'salt': 'MPWAcxbAyiVXdpeU', 'played': 20, 'lost': 5}]\n"
+     ]
     }
    ],
    "source": [