protocols.py

from abc import abstractmethod
from typing import Protocol


class Writable(Protocol):
    @abstractmethod
    def write(self, data: dict) -> None:
        """This method should write dictionary data."""


class Readable(Protocol):
    def read(self) -> dict:
        """This method should return a dictionary"""


def do_write(writer: Writable, data: dict) -> None:
    return writer.write(data)


def do_read(reader: Readable) -> dict:
    return reader.read()


class Author(Writable):
    def __init__(self, name: str) -> None:
        self.name = name

    def writable(self, data: dict) -> None:
        print(f"{self.name} is writing {data}")


def main():
    data = {"name": "John Doe", "age": 30}
    author = Author("John doe")
    do_write(author, data)


if __name__ == "__main__":
    main()