如何在discord.py中添加和创建角色？

import discord
from discord.ext import commands

intents = discord.Intents.default()
intents.members = True

bot = commands.Bot(command_prefix='!', intents=intents)

@bot.event
async def on_ready():
    print(f'Logged in as {bot.user.name}')

@bot.command()
async def add_role(ctx, role_name):
    guild = ctx.guild
    role = await guild.create_role(name=role_name)
    await ctx.send(f'Role {role.name} created!')

@bot.command()
async def assign_role(ctx, member: discord.Member, role: discord.Role):
    await member.add_roles(role)
    await ctx.send(f'Role {role.name} assigned to {member.display_name}!')

bot.run('YOUR_BOT_TOKEN')