所以我一直試圖讓機器人在成員獲得角色時宣布，我知道這段代碼可能根本沒有意義，但這就是我問的原因：我該怎么做？@bot.eventasync def on_member_update(before, after):    if str(after.roles) == 'android':        fmt = "{0.mention} your role request has been accepted! :confetti_ball: You've been granted the role '{1}'"        await bot.send_message(bot.get_channel('495285593711050754'), fmt.format(member, after.roles.name))        print(colored('moderation.clf: ', 'blue'), colored('Android granted', 'white'))    if str(after.roles) == 'human':        fmt = "{0.mention} your role request has been accepted! :confetti_ball: You've been granted the role '{1}'"        await bot.send_message(bot.get_channel('495285593711050754'), fmt.format(member, after.roles.name))        print(colored('moderation.clf: ', 'blue'), colored('Human granted', 'white'))    if str(after.roles) == 'moderator':        fmt = "{0.mention} you are now part of the CyberLife staff, we're so excited to have you here! :confetti_ball:"        await bot.send_message(bot.get_channel('495285593711050754'), fmt.format(member, after.roles.name))        print(colored('moderation.clf: ', 'blue'), colored('Moderator granted', 'white'))