Add materials for OOP update

Author: martin-martin

python-oop/README.md

@@ -0,0 +1,3 @@
+# Object-Oriented Programming (OOP) in Python 3
+
+This folder provides the code examples for the Real Python tutorial [Object-Oriented Programming (OOP) in Python 3](https://realpython.com/object-oriented-programming-oop-in-python-3/).

python-oop/cars.py

@@ -0,0 +1,14 @@
+class Car:
+    def __init__(self, color, mileage):
+        self.color = color
+        self.mileage = mileage
+
+    def __str__(self):
+        return f"The {self.color} car has {self.mileage:,} miles"
+
+
+blue_car = Car(color="blue", mileage=20_000)
+red_car = Car(color="red", mileage=30_000)
+
+for car in (blue_car, red_car):
+    print(car)

python-oop/dog.py

@@ -0,0 +1,12 @@
+class Dog:
+    species = "Canis familiaris"
+
+    def __init__(self, name, age):
+        self.name = name
+        self.age = age
+
+    def __str__(self):
+        return f"{self.name} is {self.age} years old"
+
+    def speak(self, sound):
+        return f"{self.name} says {sound}"

python-oop/dogbreeds.py

@@ -0,0 +1,25 @@
+class Dog:
+    species = "Canis familiaris"
+
+    def __init__(self, name, age):
+        self.name = name
+        self.age = age
+
+    def __str__(self):
+        return f"{self.name} is {self.age} years old"
+
+    def speak(self, sound):
+        return f"{self.name} barks: {sound}"
+
+
+class JackRussellTerrier(Dog):
+    def speak(self, sound="Arf"):
+        return super().speak(sound)
+
+
+class Dachshund(Dog):
+    pass
+
+
+class Bulldog(Dog):
+    pass

python-oop/retriever.py

@@ -0,0 +1,17 @@
+class Dog:
+    species = "Canis familiaris"
+
+    def __init__(self, name, age):
+        self.name = name
+        self.age = age
+
+    def __str__(self):
+        return f"{self.name} is {self.age} years old"
+
+    def speak(self, sound):
+        return f"{self.name} says {sound}"
+
+
+class GoldenRetriever(Dog):
+    def speak(self, sound="Bark"):
+        return super().speak(sound)

python-oop/starfleet_list.py

@@ -0,0 +1,5 @@
+# Starfleet employees as a list
+
+kirk = ["James Kirk", 34, "Captain", 2265]
+spock = ["Spock", 35, "Science Officer", 2254]
+mccoy = ["Leonard McCoy", "Chief Medical Officer", 2266]

python-oop/starfleet_objects.py

@@ -0,0 +1,14 @@
+# Starfleet employees as objects
+
+
+class Employee:
+    def __init__(self, name, age, position, year_started):
+        self.name = name
+        self.age = age
+        self.position = position
+        self.year_started = year_started
+
+
+kirk = Employee("James Kirk", 34, "Captain", 2265)
+spock = Employee("Spock", 35, "Science Officer", 2254)
+mccoy = Employee("Leonard McCoy", 137, "Chief Medical Officer", 2266)