with open(file_name, 'rb') as fp:
    data = io.BytesIO(fp.read())
file = discord.File(data, file_name)

import logging
import sys
from io import StringIO

import discord
from discord.ext import commands, pages

logging.basicConfig(stream=sys.stdout, level=logging.INFO)

class Bot(commands.Bot):
    def __init__(self):
        super().__init__(command_prefix = '.', intents=discord.Intents.all())

bot = Bot()

@bot.slash_command()
async def teststringio(
    ctx: discord.ApplicationContext, 
): 
    test = discord.Embed(title="test", description="test")
    
    p = []
    for i in range(5):
        p.append(pages.Page(embeds=[test], files=[discord.File(StringIO(f"{i}"), f"test{i}.txt")]))
    paginator = pages.Paginator(pages=p, disable_on_timeout=True)
    await paginator.respond(ctx.interaction)
    
@bot.slash_command()
async def testreadingbuffer(
    ctx: discord.ApplicationContext, 
): 
    test = discord.Embed(title="test", description="test")
    
    p = []
    for i in range(5):
        p.append(pages.Page(embeds=[test], files=[discord.File(f"test{i}.txt")]))
    paginator = pages.Paginator(pages=p, disable_on_timeout=True)
    await paginator.respond(ctx.interaction)
            
bot.run("token")