os module error

import os
import discord
from discord.ext import commands
from fastapi import FastAPI
import asyncio
from pydantic import BaseModel


token = 'Discord Bot Token'
app=FastAPI()
client = commands.Bot(command_prefix='!')

class Item(BaseModel):
    name:str
    price:float
    brand:str

@app.get('/')
async def hello():
    return {'Hello':'You'}

client.event
async def on_ready():
    print(f"Logged in as {client.user} Running with FastAPI")

@client.command()
async def welcome(ctx:commands.Context,member:discord.Member):
    await ctx.send(f"Welcome to {ctx.guild.name}")

async def run():
    try:
        await client.start(token)
    except KeyboardInterrupt:
        await client.logout()

@app.put('/item/{item_id}')
async def get_item(item_id:int,item:Item):
    result={'item_id':item_id,'item':item}
    return result

@client.command()
async def load(ctx,extension):
    client.load_extension(f"Cogs.{extension}")
#asyncio.create_task(run())

@client.command()
async def unload(ctx,extension):
    client.unload_extension(f"Cogs.{extension}")

for filename in os.listdir('./Cogs'):
    if filename.endswith('.py'):
        client.load_extension(f'Cogs.{filename[:-3]}')

client.run(token)