python-isinstance (Fix)

python-isinstance/README.md

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+# What Does isinstance() Do in Python?
+
+This folder provides the code examples for the Real Python tutorial [What Does isinstance() Do in Python?](https://realpython.com/what-does-isinstance-do-in-python/).
+
+The `.py` files contain the code found in the tutorial. 
+
+When setting up your tutorial environment, make sure `balls.py`, `balls_v2.py`, and `player_iterables.py` are in your program folder.  You'll need to import content from these to replicate the tutorial examples.

python-isinstance/abstract_class_failure.py

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+from balls_v2 import Ball
+
+test_ball = Ball("white", "sphere")

python-isinstance/ball_instance_test.py

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+from balls import AmericanFootBall, Ball, PoolBall
+
+eight_ball = PoolBall("black", 8)
+football = AmericanFootBall("brown")
+ball = Ball("green", "sphere")
+
+isinstance(eight_ball, PoolBall)
+isinstance(eight_ball, Ball)
+isinstance(eight_ball, AmericanFootBall)
+
+isinstance(eight_ball, object)
+isinstance(football, object)
+isinstance(ball, object)
+isinstance(object, object)

python-isinstance/balls.py

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+class Ball:
+    def __init__(self, color, shape):
+        self.color = color
+        self.shape = shape
+
+
+class PoolBall(Ball):
+    def __init__(self, color, number):
+        super().__init__(color, shape="sphere")
+        self.number = number
+
+
+class AmericanFootBall(Ball):
+    def __init__(self, color):
+        super().__init__(color, shape="prolate spheroid")

python-isinstance/balls_v2.py

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+from abc import ABC, abstractmethod
+
+
+class Ball(ABC):
+    def __init__(self, color, shape):
+        self.color = color
+        self.shape = shape
+
+    @abstractmethod
+    def get_state(self):
+        pass
+
+
+class PoolBall(Ball):
+    def __init__(self, color, number):
+        super().__init__(color, shape="sphere")
+        self.number = number
+
+    def get_state(self):
+        print(
+            f"Color = {self.color}, Number = {self.number}, Shape = {self.shape}"
+        )
+
+
+class AmericanFootBall(Ball):
+    def __init__(self, color):
+        super().__init__(color, shape="prolate spheroid")
+
+    def get_state(self):
+        print(f"Color = {self.color}, Shape = {self.shape}")

python-isinstance/basic_types.py

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+shape = "Sphere"
+number = 8
+
+isinstance(shape, str)
+isinstance(number, int)
+isinstance(number, float)

python-isinstance/bool_int_test.py

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+isinstance(True, int)
+
+isinstance(True, bool)
+
+isinstance(False, int)
+
+isinstance(False, bool)
+
+test_data = [10, True, False]
+
+for element in test_data:
+    print("int") if isinstance(element, int) else print("bool")
+
+for element in test_data:
+    print("bool") if isinstance(element, bool) else print("int")
+
+for element in test_data:
+    print("bool") if type(element) is bool else print("int")  # noqa

python-isinstance/calculate_area_v1.py

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+def calculate_area(length, breadth):
+    return length * breadth
+
+
+calculate_area(5, 3)
+calculate_area(5, "3")
+calculate_area("5", "3")

python-isinstance/calculate_area_v2.py

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+def calculate_area(length, breadth):
+    if isinstance(length, int) and isinstance(breadth, int):
+        return length * breadth
+    raise TypeError("Both arguments must be integers")
+
+
+calculate_area(5, 3)
+calculate_area(5, "3")
+calculate_area("5", "3")

python-isinstance/consolidation1_solution.py

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+from balls import AmericanFootBall, Ball, PoolBall
+
+ball = Ball("green", "sphere")
+football = AmericanFootBall("brown")
+
+isinstance(football, AmericanFootBall)
+
+isinstance(football, PoolBall)
+
+isinstance(ball, Ball)
+
+isinstance(ball, AmericanFootBall)
+
+isinstance(football, Ball)
+
+isinstance(ball, PoolBall)
+
+isinstance(1, bool)
+
+isinstance(0, bool)

python-isinstance/consolidation2_solution.py

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+from abc import ABC
+from collections.abc import Callable
+
+from balls_v2 import AmericanFootBall, PoolBall
+
+eight_ball = PoolBall("black", 8)
+football = AmericanFootBall("brown")
+
+# a)
+
+isinstance(eight_ball, ABC)
+isinstance(football, ABC)
+
+# b)
+
+isinstance(isinstance, Callable)
+isinstance(PoolBall, Callable)
+
+# c)
+
+isinstance(eight_ball.get_state, Callable)
+
+isinstance(PoolBall, Callable)

python-isinstance/isinstance_vs_type.py

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+from balls import Ball, PoolBall
+
+eight_ball = PoolBall("black", 8)
+
+type(eight_ball)
+
+type(eight_ball) is PoolBall
+
+isinstance(eight_ball, Ball)
+
+type(eight_ball) is Ball

python-isinstance/isinstance_with_abc.py

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+from balls_v2 import AmericanFootBall, Ball, PoolBall
+
+eight_ball = PoolBall("black", 8)
+
+football = AmericanFootBall("brown")
+
+isinstance(eight_ball, Ball)
+
+isinstance(football, Ball)

python-isinstance/iter_test.py

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+from player_iterables import (
+    PlayersVersionFour,
+    PlayersVersionOne,
+    PlayersVersionThree,
+    PlayersVersionTwo,
+)
+
+iter(PlayersVersionOne(["Fast Ed", "Slow Jo", "Still Su"]))
+
+iter(PlayersVersionTwo(["Fast Ed", "Slow Jo", "Still Su"]))
+
+iter(PlayersVersionThree(["Fast Ed", "Slow Jo", "Still Su"]))
+
+iter(PlayersVersionFour(["Fast Ed", "Slow Jo", "Still Su"]))

python-isinstance/mro.py

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+class Top:
+    pass
+
+
+class Middle(Top):
+    pass
+
+
+class Bottom(Middle):
+    pass
+
+
+Bottom.mro()
+isinstance(Bottom(), Top)

python-isinstance/multiple_type_tests.py

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+print("Number" if isinstance(3.14, (int, float)) else "Not a number")
+
+print("Number" if isinstance("3.14", (int, float)) else "Not a number")
+
+print("Number" if isinstance(3.14, ((int,), (float,))) else "Not a number")
+
+print("Number" if isinstance(3.14, (int, float)) else "Not a number")
+
+print("Number" if isinstance(3.14, int | float) else "Not a number")
+
+print("Number" if isinstance("3.14", int | float) else "Not a number")

python-isinstance/player_iterables.py

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+from collections.abc import Iterable
+
+
+class PlayersVersionOne(Iterable):
+    def __init__(self, players):
+        self.players = players
+
+    def __iter__(self):
+        return iter(self.players)
+
+
+class PlayersVersionTwo:
+
+    def __init__(self, players):
+        self.players = players
+
+    def __iter__(self):
+        return iter(self.players)
+
+
+class PlayersVersionThree:
+
+    def __init__(self, players):
+        self.players = players
+
+    def __getitem__(self, index):
+        if index >= len(self.players):
+            raise IndexError
+        return self.players[index]
+
+
+class PlayersVersionFour:
+
+    def __init__(self, players):
+        self.players = players
+
+    def __iter__(self):
+        pass

python-isinstance/players_iterable_tests.py

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+from collections.abc import Iterable
+
+from player_iterables import (
+    PlayersVersionFour,
+    PlayersVersionOne,
+    PlayersVersionThree,
+    PlayersVersionTwo,
+)
+
+for player in PlayersVersionOne(["Fast Ed", "Slow Jo", "Still Su"]):
+    print(player)
+
+isinstance(PlayersVersionOne(["Fast Ed", "Slow Jo", "Still Su"]), Iterable)
+
+for player in PlayersVersionTwo(["Fast Ed", "Slow Jo", "Still Su"]):
+    print(player)
+
+isinstance(PlayersVersionTwo(["Fast Ed", "Slow Jo", "Still Su"]), Iterable)
+
+for player in PlayersVersionThree(["Fast Ed", "Slow Jo", "Still Su"]):
+    print(player)
+
+isinstance(PlayersVersionThree(["Fast Ed", "Slow Jo", "Still Su"]), Iterable)
+
+# This will fail.
+for player in PlayersVersionFour(["Fast Ed", "Slow Jo", "Still Su"]):
+    print(player)
+
+isinstance(PlayersVersionFour(["Fast Ed", "Slow Jo", "Still Su"]), Iterable)

python-isinstance/type_tests.py

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+from balls import Ball, PoolBall
+
+eight_ball = PoolBall("black", 8)
+
+type(eight_ball)
+
+type(eight_ball) is PoolBall
+
+
+isinstance(eight_ball, Ball)
+
+type(eight_ball) is Ball