update PythonObjects; add singleton

Author: rambasnet

notebooks/PythonObjects.ipynb

@@ -1315,7 +1315,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 41,
+   "execution_count": null,
    "id": "4e8f863a",
    "metadata": {},
    "outputs": [],
@@ -1327,7 +1327,7 @@
     "\n",
     "    # singleton pattern\n",
     "    def __new__(cls, *args, **kwargs):\n",
-    "        # we don't care about args and kwargs within __new__\n",
+    "        # we don't care about (a, b) so use args and kwargs within __new__\n",
     "        # not providing them will create syntax error because __init__ is defined with two arguments \n",
     "        if not cls._instance:\n",
     "            cls._instance = super().__new__(cls)\n",
@@ -1346,7 +1346,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 42,
+   "execution_count": 52,
    "id": "a764ca44",
    "metadata": {},
    "outputs": [],
@@ -1357,7 +1357,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 43,
+   "execution_count": 53,
    "id": "b9b63da3",
    "metadata": {},
    "outputs": [
@@ -1367,7 +1367,7 @@
        "True"
       ]
      },
-     "execution_count": 43,
+     "execution_count": 53,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -1378,7 +1378,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 44,
+   "execution_count": 54,
    "id": "b302bf1f",
    "metadata": {},
    "outputs": [
@@ -1398,7 +1398,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 45,
+   "execution_count": 55,
    "id": "ad9b3855",
    "metadata": {},
    "outputs": [
@@ -1408,7 +1408,7 @@
        "True"
       ]
      },
-     "execution_count": 45,
+     "execution_count": 55,
      "metadata": {},
      "output_type": "execute_result"
     }