import asyncio
from pyrogram.parser.parser import Parser

parser = Parser(None)

samples = ["__Italic text__", "**Bold text**"]
# samples = ["<i>Italic text</i>", "<b>Bold text</b>"]

async def main():
    for sample in samples:
        message, entities = (await parser.parse(text=sample)).values()

        print(message, entities)

        res = parser.unparse(text=message, entities=entities, is_html=False)  # AttributeError: 'MessageEntityItalic' object has no attribute 'type'

        print(res)


asyncio.run(main())