How to ban by username and id?

Question

Python

Hello!
I wrote a command that, according to the idea, should ban a participant by username or his id, but something does not work.
Tell me what's wrong, please.

@commands.command()
async def ban(self, ctx, member, *, reason=None):
        if len(member) == 18 and member.isdigit() == True: # бан по id участника
            id = int(member)
            user = await self.client.fetch_user(id)
            await user.ban(reason = reason)
        else: # бан по username участника
            await member.ban(reason = reason)

Answer 1

Use converters :

import typing

...

@commands.command()
async def ban(self, ctx, member: typing.Union[discord.Member, int], *, reason=None):
# https://discordpy.readthedocs.io/en/stable/ext/commands/commands.html#typing-union
    if isinstance(member, int):
        member = discord.Object(member)
    try:
        await ctx.guild.ban(member, reason=reason)  # https://discordpy.readthedocs.io/en/stable/api.html#discord.Guild.ban
    except NotFound:
        await ctx.send(f"Не найдено пользователя с ID {member.id}")