我正在使用 [这个 q2a 导入](https://gist.github.com/[Communiteq](https://www.communiteq.com) (formerly DiscourseHosting)/769eff2014d5482f0ab776de03dc3349) 脚本,并看到以下错误。请帮忙解决此问题。
这是用户库的问题还是脚本的问题?如何修复?谢谢!
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正在导入用户
80 / 447 ( 17.9%) [208 项/分钟] 回溯(最近一次调用最后):
12: from script/import_scripts/question2answer.rb:601:in `\u003cmain\u003e'
11: from /var/www/discourse/script/import_scripts/base.rb:47:in `perform'
10: from script/import_scripts/question2answer.rb:70:in `execute'
9: from script/import_scripts/question2answer.rb:89:in `import_users'
8: from /var/www/discourse/script/import_scripts/base.rb:877:in `batches'
7: from /var/www/discourse/script/import_scripts/base.rb:877:in `loop'
6: from /var/www/discourse/script/import_scripts/base.rb:878:in `block in batches'
5: from script/import_scripts/question2answer.rb:106:in `block in import_users'
4: from /var/www/discourse/script/import_scripts/base.rb:247:in `create_users'
3: from /var/www/discourse/script/import_scripts/base.rb:247:in `each'
2: from /var/www/discourse/script/import_scripts/base.rb:259:in `block in create_users'
1: from /var/www/discourse/script/import_scripts/base.rb:290:in `create_user'
/var/www/discourse/script/import_scripts/base.rb:393:in `find_existing_user': undefined method `downcase' for nil:NilClass (NoMethodError)