Versioned Class

class_03.py

"""
A versioned class example.
"""
__version__: str = "0.1"

class Book:
    """
    A sinple book class.
    """
    counter: int = 0
    __class_version__: str = __version__

    def __init__(self, isbn: str, title: str, author: str):
        """
        The constructor
        """
        self.isbn = isbn
        self.title = title
        self.author = author
        self.page = 0
        self.notes = []
        type(self).counter += 1
        self.sequencenumber: int = type(self).counter

    @property
    def version(self):
        """
        Returns the Class version, not an object's version.
        """
        return type(self).__class_version__

    def set_note(self, note: str, page: int)-> int:
        """
        Sets a reader note.
        """
        self.notes.append((note, page))

    def goto_page(self, page_number: int):
        """
        Sets the current page number. Maximum of 1000.
        """
        if page_number < 1000 > 0:
            self.page = page_number

    def __repr__(self) -> str:
        return (f"Object id: {id(self)}. Version: {self.version}, "
                f"ObjSeq: {self.sequencenumber}, Total created: {Book.counter}, "
                f"Author: {self.author}, "
                f"Title: {self.title}. ISBN: {self.isbn}.")