#Python's member visibility

You can access object members through object.member:

# Define class
class Cat:
    """
    Cat class
    """

    def __init__(self, name: str):
        """
        Constructor

        Args:
            name (str): Name
        """

        self.name = name   # Create name attribute

# Create a group of cats
cat1 = Cat("Tom")
cat2 = Cat("Happy")
cat3 = Cat("San San")

# Access name attribute
print(cat1.name)
print(cat2.name)
print(cat3.name)

# Modify name attribute
cat1.name = 'Schrödinger'
print(cat1.name)
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#Private Members

Private variables can only be accessed by the object that owns them, i.e., they can only be read or modified through the object's own methods. Recall the naming conventions:

• Private variables use two leading underscores, e.g., __age_of_yukari

Methods can also be made private using this naming style.

For example, to make the cat's name a private attribute, provide a name method to read it and a set_name method to modify it, and forbid naming the cat "Schrödinger":

# Define class
class Cat:
    """
    Cat class
    """

    def __init__(self, name: str):
        """
        Constructor

        Args:
            name (str): Name
        """

        self.__name = name   # Create private __name attribute

    def name(self) -> str:
        """
        name method to get the cat's name

        Returns:
            str: The cat's name
        """
        return self.__name

    def set_name(self, name: str) -> bool:
        """
        set_name method to set the cat's name

        Args:
            name (str): Name to set

        Returns:
            bool: Whether setting the name was successful
        """

        if name == "Schrödinger":
            return False

        self.__name = name
        return True


# Create object
cat = Cat("Garfield")
print(cat.name())

# Try to access __name directly
try:
    print('Directly reading __name succeeded:', cat.__name)
except Exception as e:
    print('Directly reading __name failed')

# Try setting name to Schrödinger
cat.set_name("Schrödinger")
print(cat.name())
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This shows how to control member visibility in Python classes using private attributes and methods.