Merge pull request #679 from realpython/type-hint-arrow-samples

Type hint arrow samples

Author: brendaweles

what-does-arrow-mean-in-python/README.md

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+This folder provides the code examples for the Real Python tutorial [What Does -> Mean in Python Function Definitions?](https://realpython.com/what-does-mean-in-python-function-definitions/) 

what-does-arrow-mean-in-python/dictionary_return_type_example.py

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+game_stock = {"Dragon Quest": 5, "Final Fantasy": 1, "Age of Empires": 5}
+
+
+def get_highest_stock_games(game_stock: dict[str, int]) -> dict[str, int]:
+    max_quantity = max(game_stock.values())
+    return {
+        game: quantity
+        for game, quantity in game_stock.items()
+        if quantity == max_quantity
+    }
+
+
+print(f"Games with the highest stock: {get_highest_stock_games(game_stock)}")

what-does-arrow-mean-in-python/dynamic_variable_example.py

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+my_number = 32
+my_number = "32"

what-does-arrow-mean-in-python/game_class_example.py

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+class Game:
+    def __init__(self, name: str, genre: str, price: float) -> None:
+        self.name = name
+        self.genre = genre
+        self.price = price
+
+    def get_name(self) -> str:
+        return self.name
+
+    def get_genre(self) -> str:
+        return self.genre
+
+    def get_price(self) -> float:
+        return self.price

what-does-arrow-mean-in-python/mismatched_return_type_example.py

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+def get_number_of_titles(titles: list[str]) -> str:
+    return len(titles)
+
+
+games = ["Dragon Quest", "Final Fantasy", "Age of Empires"]
+print(f"Number of titles: {get_number_of_titles(games)}")

what-does-arrow-mean-in-python/none_return_type_hint_example.py

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+def find_keyword_in_titles(titles: list[str], keyword: str) -> None:
+    print(f"Titles that contain the keyword {keyword}")
+    for game_title in titles:
+        if keyword in game_title:
+            print(f"{game_title}")
+
+
+games = ["Dragon Quest", "Final Fantasy", "Age of Empires"]
+find_keyword_in_titles(games, "Final")

what-does-arrow-mean-in-python/simple_type_hint_example.py

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+def get_number_of_titles(titles: list[str]) -> int:
+    return len(titles)
+
+
+games = ["Dragon Quest", "Final Fantasy", "Age of Empires"]
+print(f"Number of titles: {get_number_of_titles(games)}")

what-does-arrow-mean-in-python/str_return_type_hint_example.py

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+import random
+
+
+def get_game_recommendation(titles: list[str]) -> str:
+    return random.choice(titles)
+
+
+games = ["Dragon Quest", "Final Fantasy", "Age of Empires"]
+print(f"Random recommendation: {get_game_recommendation(games)}")