You have to pass in a name to the @commands.command()
decorator.
@commands.command(name='ban', description='Bans a user')
@commands.has_permissions(ban_members=True)
async def ban(self, ctx, member: discord.Member, *, reason=None):
await member.ban(reason=reason)
await ctx.send(f'User {member} has been kick')
And the first client variable isn't needed as you are declaring another client variable the line after it and it doesn't do much.
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