Remove some old presentations

2 files changed, 79 insertions, 30 deletions

diff --git a/notebooks/python/python_intro.ipynb b/notebooks/python/python_intro.ipynb
index 3c49a14..0168839 100644
--- a/notebooks/python/python_intro.ipynb
+++ b/notebooks/python/python_intro.ipynb
@@ -1253,7 +1253,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.8"
+   "version": "3.11.1"
   }
  },
  "nbformat": 4,
diff --git a/notebooks/python/python_oo.ipynb b/notebooks/python/python_oo.ipynb
index b56aa26..1c655d0 100644
--- a/notebooks/python/python_oo.ipynb
+++ b/notebooks/python/python_oo.ipynb
@@ -179,7 +179,8 @@
     "\"The Zen of Python\" (import this) is still relevant and should be followed :)\n",
     "\n",
     "\"Python will remain a dynamically typed language, and the authors have no desire to ever make type hints mandatory, even by convention.\" - PEP484\n",
-    "\n"
+    "\n",
+    "Class (type) names should normally use the *CapWords* convention - CapitalizedWords (or *CapWords*, or *CamelCase*). This is also sometimes known as *StudlyCaps*. ASCII characters and English names only!"
    ]
   },
   {
@@ -225,17 +226,17 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "car1.get_obj_info_str() = \"I am <__main__.Car object at 0x7f5630542810> with id 140008154736656 from <class '__main__.Car'> with id 94904583728688\"\n",
-      "car2.get_obj_info_str() = \"I am <__main__.Car object at 0x7f5633ec8190> with id 140008215052688 from <class '__main__.Car'> with id 94904583728688\"\n",
-      "car1.model = 'BMW', car1.reg_nr = 'EC76183', car1.extras = ['GPSnav', 'Sound system'], id(car1.cls_extras) = 140008154734272, id(car1.__init__) = 140008154735680\n",
-      "car2.model = 'Scoda', car2.reg_nr = 'BD77655', car2.extras = ['GPSnav'], id(car2.cls_extras) = 140008154734272, id(car2.__init__) = 140008154736768\n",
-      "id(Car.cls_extras) = 140008154734272, id(Car.__init__) = 140008154484864\n",
-      "car1.cls_extras = ['GPSnav', 'Sound system'], id(car1.cls_extras) = 140008154734272\n",
-      "car2.cls_extras = ['GPSnav', 'Sound system'], id(car2.cls_extras) = 140008154734272\n",
+      "car1.get_obj_info_str() = \"I am <__main__.Car object at 0x7fc7add96f10> with id 140495591927568 from <class '__main__.Car'> with id 94628241379728\"\n",
+      "car2.get_obj_info_str() = \"I am <__main__.Car object at 0x7fc7aef459d0> with id 140495610468816 from <class '__main__.Car'> with id 94628241379728\"\n",
+      "car1.model = 'BMW', car1.reg_nr = 'EC76183', car1.extras = ['GPSnav', 'Sound system'], id(car1.cls_extras) = 140495591909184, id(car1.get_obj_info_str) = 140495591927808\n",
+      "car2.model = 'Scoda', car2.reg_nr = 'BD77655', car2.extras = ['GPSnav'], id(car2.cls_extras) = 140495591909184, id(car2.get_obj_info_str) = 140495591927936\n",
+      "id(Car.cls_extras) = 140495591909184, id(Car.get_obj_info_str) = 140495591682944\n",
+      "car1.cls_extras = ['GPSnav', 'Sound system'], id(car1.cls_extras) = 140495591909184\n",
+      "car2.cls_extras = ['GPSnav', 'Sound system'], id(car2.cls_extras) = 140495591909184\n",
       "True\n",
       "hasattr(car1, 'import_tax_paid') = True\n",
       "hasattr(car2, 'import_tax_paid') = False\n",
-      "id(car1.__class__) = 94904583728688, id(car2.__class__) = 94904583728688, id(Car) = 94904583728688\n"
+      "id(car1.__class__) = 94628241379728, id(car2.__class__) = 94628241379728, id(Car) = 94628241379728\n"
      ]
     }
    ],
@@ -244,6 +245,7 @@
     "\n",
     "    cls_extras = []  # class attribute - shared by all instances\n",
     "    # cls_extras: list = [] is also possible\n",
+    "    car_count = 0\n",
     "\n",
     "    def __init__(self, model: str, reg_nr: str, extras: list):\n",
     "        \"\"\"\n",
@@ -262,24 +264,40 @@
     "\n",
     "        # self.cls_extras = extras  # will create a *NEW instance attribute* called 'cls_extras'\n",
     "        \n",
+    "        Car.car_count += 1  # increase Car.car_count by 1 every time a car is created \n",
+    "    \n",
+    "    def __del__(self):\n",
+    "        \"\"\"\n",
+    "        Called when the instance is about to be destroyed.\n",
+    "\n",
+    "        This is also called a finalizer or (improperly) a destructor.\n",
+    "        \"\"\"\n",
+    "        Car.car_count -= 1  # decrease by 1 every time a Car object is destroyed\n",
+    "\n",
     "    def get_obj_info_str(self):  # regular method that becomes instance attribute\n",
     "        return f\"I am {self} with id {id(self)} from {self.__class__} with id {id(self.__class__)}\"\n",
     "\n",
     "car1 = Car(\"BMW\", \"EC76183\", [\"GPSnav\", \"Sound system\"])\n",
     "car2 = Car(\"Scoda\", \"BD77655\", [\"GPSnav\"])\n",
     "\n",
-    "print(f\"{car1.get_obj_info_str() = }\")\n",
+    "print(f\"{car1.get_obj_info_str() = }\")  # same as calling Car.get_object_info_str(car1)\n",
     "print(f\"{car2.get_obj_info_str() = }\")\n",
     "\n",
     "# default behavior for `object.attr`:\n",
     "# getter:\n",
     "#     - checks if 'attr' is an instance attribute\n",
-    "#     - checks if 'attr' is a class attribute\n",
+    "#     - checks if 'attr' is a class attribute (through the method resolution order - MRO)\n",
     "#     - raises AttributeError\n",
-    "# setter: (re)defines an instance attribute\n",
-    "print(f\"{car1.model = }, {car1.reg_nr = }, {car1.extras = }, {id(car1.cls_extras) = }, {id(car1.__init__) = }\")\n",
-    "print(f\"{car2.model = }, {car2.reg_nr = }, {car2.extras = }, {id(car2.cls_extras) = }, {id(car2.__init__) = }\")\n",
-    "print(f\"{id(Car.cls_extras) = }, {id(Car.__init__) = }\")\n",
+    "# setter:\n",
+    "#     - (re)defines an instance attribute\n",
+    "\n",
+    "# Details not covered in this course:\n",
+    "# Car.x is translated to Car.__dict__[\"x\"] (...through the MRO)\n",
+    "# car1.x is translated to car1.__dict__[\"x\"] (if not found ... Car.x (see above), if not found car1.__getattr__(\"x\") is called)\n",
+    "\n",
+    "print(f\"{car1.model = }, {car1.reg_nr = }, {car1.extras = }, {id(car1.cls_extras) = }, {id(car1.get_obj_info_str) = }\")\n",
+    "print(f\"{car2.model = }, {car2.reg_nr = }, {car2.extras = }, {id(car2.cls_extras) = }, {id(car2.get_obj_info_str) = }\")\n",
+    "print(f\"{id(Car.cls_extras) = }, {id(Car.get_obj_info_str) = }\")\n",
     "car1.cls_extras.extend(car1.extras)\n",
     "# car1.cls_extras = car1.extras  # N.B. This will create a *NEW instance attribute* called 'cls_extras'\n",
     "print(f\"{car1.cls_extras = }, {id(car1.cls_extras) = }\")\n",
@@ -289,7 +307,7 @@
     "car1.import_tax_paid = True  # 'import_tax_paid' will only be present in car1\n",
     "print(car1.import_tax_paid)\n",
     "print(f\"{hasattr(car1, 'import_tax_paid') = }\")  # Out: True\n",
-    "print(f\"{hasattr(car2, 'import_tax_paid') = }\")  # Out: False\n",
+    "print(f\"{hasattr(car2, 'import_tax_paid') = }\")  # Out: False - no 'import_tax_paid' attribute in object car2\n",
     "\n",
     "# .__class__ instance attribute pointing to its class (type) will be created\n",
     "print(f\"{id(car1.__class__) = }, {id(car2.__class__) = }, {id(Car) = }\")"
@@ -705,6 +723,7 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
+      "2:2\n",
       "__mul__ called\n",
       "vector * 3 = Vector(start=Point(x=2, y=2), end=Point(x=12, y=18))\n",
       "__rmul__ called\n",
@@ -771,6 +790,7 @@
     "    # __rmul__ = __mul__\n",
     "\n",
     "vector = Vector(Point(2, 2), Point(4, 6))\n",
+    "print(f\"{vector['start']}\")\n",
     "print(f\"{vector * 3 = }\")\n",
     "print(f\"{3 * vector = }\")"
    ]
@@ -863,7 +883,7 @@
    "id": "d1d17f26-de6e-4510-b0f0-3ae02761ae24",
    "metadata": {},
    "source": [
-    "# Example 2\n",
+    "# Example 3\n",
     "\n",
     "We will create a small and incomplete Animal class hierarchy"
    ]
@@ -973,7 +993,7 @@
     "        super().__init__(\n",
     "            weight=weight, tooth_replacement=True, alive=alive, **kwargs\n",
     "        )\n",
-    "        self_conservation_status = conservation_status\n",
+    "        self._conservation_status = conservation_status\n",
     "\n",
     "\n",
     "class Cow(Mammal):\n",
@@ -1104,6 +1124,7 @@
     "    \"\"\"\n",
     "\n",
     "\n",
+    "# not good! The user of JSONMixin should not have to explicitly know about / use DictMixin\n",
     "class JSONConvertableTigerShark(TigerShark, DictMixin, JSONMixin):\n",
     "    \"\"\"A tiger shark class that provides JSON conversion functionality\"\"\"\n",
     "\n",
@@ -1143,14 +1164,7 @@
     "MRO is monotonic when the following is true: if C1 precedes C2 in the linearization of C, then C1 precedes C2 in the linearization of any subclass of C.\n",
     "\n",
     "Not all classes admit a linearization. There are cases, in complicated hierarchies, where it is not possible to derive a class such that its linearization respects all the desired properties.  \n",
-    "`TypeError: Cannot create a consistent method resolution order (MRO) for bases X, Y` is raised then.\n",
-    "\n",
-    "\n",
-    "## The Liskov substitution principle (LSP):\n",
-    "\n",
-    "Functions that use references to base class objects must be able to use objects of derived classes without knowing it.\n",
-    "\n",
-    "In other words: an object (such as a class) may be replaced by a sub-object (such as a class that extends the first class) without breaking the program.\n"
+    "`TypeError: Cannot create a consistent method resolution order (MRO) for bases X, Y` is raised then."
    ]
   },
   {
@@ -1233,6 +1247,14 @@
    ]
   },
   {
+   "cell_type": "markdown",
+   "id": "875e7ffd-4feb-4ef0-b912-0a939c6c2dd1",
+   "metadata": {},
+   "source": [
+    "... **N.B.** The most important thing to note here is that if `super()` is used in `Grandfather1` for this MRO (f.i. object of type `Simeon`) , none of its parents or siblings is called, but `Father` that was probably \"not even born\" when `Grandfather1` was created. :)"
+   ]
+  },
+  {
    "cell_type": "code",
    "execution_count": 12,
    "id": "95a1d0cc-0006-4ddc-b08d-d0b8b02acfba",
@@ -1274,7 +1296,6 @@
     "    \"\"\"Produces JSON content for production plans\"\"\"\n",
     "    \n",
     "    def to_json(self, **kwargs):\n",
-    "        # super().get_data(**kwargs)\n",
     "        self.get_data(**kwargs)\n",
     "        prod_plans = self.extract_production_plans(**kwargs)\n",
     "        return json.dumps(self.__do_some_magic(prod_plans), indent=kwargs.get(\"indent\", 2))\n",
@@ -1295,7 +1316,10 @@
     "\n",
     "\n",
     "cool_ts_proprocessor = CoolTSPreprocessor()\n",
-    "print(cool_ts_proprocessor.to_json(indent=4))"
+    "print(cool_ts_proprocessor.to_json(indent=4))\n",
+    "\n",
+    "# but we want to test CoolTSPreprocessor without the annoying ConnectionManager.get_data method being used\n",
+    "# simply (temporary or canditionally) replacing ConnectionManager with MockConnectionManager will go against the O in SOLID"
    ]
   },
   {
@@ -1311,6 +1335,7 @@
       "Using mock data\n",
       "Extracting production plans from data\n",
       "some magic is happening here...\n",
+      "{}\n",
       "(<class '__main__.MockedButStillCoolTSPreprocessor'>, <class '__main__.CoolTSPreprocessor'>, <class '__main__.MockConnectionManager'>, <class '__main__.ConnectionManager'>, <class 'object'>)\n"
      ]
     }
@@ -1320,12 +1345,36 @@
     "    pass\n",
     "\n",
     "mocked_but_still_cool_ts_preprocessor = MockedButStillCoolTSPreprocessor()\n",
-    "mocked_but_still_cool_ts_preprocessor.to_json(indent=4)\n",
+    "print(mocked_but_still_cool_ts_preprocessor.to_json(indent=4))\n",
     "print(MockedButStillCoolTSPreprocessor.__mro__)"
    ]
   },
   {
    "cell_type": "markdown",
+   "id": "738b9084-27b9-4837-a927-e2087267d483",
+   "metadata": {},
+   "source": [
+    "# Quick tips and final words\n",
+    "\n",
+    "- Avoid the classical pitfall: \"I am solving simple problems by simple means (the way I am used to) and could probably use OO when solving more complex problems\"! Solving simple problems is the best way to get used to the OO way of thinking / designing code.\n",
+    "\n",
+    "- Take some time to analyze and design your solution and discuss it with other team members and more experienced programmers. Do not rely only on QA (merge requests)!\n",
+    "\n",
+    "- Learn to think in terms of objects, like in real world objects (f.i. Car, Animal, TimeSeries, ProductionPlan, DataSource...)!\n",
+    "\n",
+    "- Learn to think in terms of abstract classes (types): Classes that will only serve as a foundation to their child classes, but will themselves never be directly instanciated!\n",
+    "\n",
+    "- Do not create \"thin\" classes / objects that simply containin some relevant attributes, protected by corresponding properties! The entire functionality (business logic) of the object should be encapsulated there.\n",
+    "\n",
+    "- Always make sure that you are not violating some of the SOLID principles (and others described above)! Run \"mental tests\" to test your current design!\n",
+    "\n",
+    "- Consider composition (\"has-a\" relationship) before considering inhiritance (\"is-a\" relationship)!\n",
+    "\n",
+    "- Read and learn from free software projects written in Python (f.i. on github.com)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
    "id": "540de317-ba77-4f5c-97ba-f1c0bec071fb",
    "metadata": {},
    "source": [