What are the differences between access modifiers public, protected, and private in programming languages?

In Python, there are no strict access modifiers like in some other languages (e.g., Java or C++), but there are conventions:

• public — attributes and methods accessible everywhere. Just regular names.
• protected — denoted by a single underscore _name. This convention indicates that the attribute or method is intended for internal use within the class and its subclasses, but is technically accessible from outside.
• private — denoted by double underscores __name. This triggers name mangling, which makes it more difficult to access the attribute from outside the class, but does not make it completely inaccessible.

Example:

class MyClass:
    def __init__(self):
        self.public = 1
        self._protected = 2
        self.__private = 3

obj = MyClass()
print(obj.public)       # 1
print(obj._protected)   # 2 (but it’s not recommended to do so)
# print(obj.__private)  # Error
print(obj._MyClass__private)  # 3, access via name mangling