我正在尝试删除除字母以外的最后一个字符：
support.help1.com,,
support.help1.com.
support.help1.com9
support.help1.com*
support.help1.com@@
support.help1.com##
support.help1.com%%
support.help1.com^
support.help1.com
support.help1.com,
support.help1.com-
我希望我的输出是这样的：
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com
support.help1.com