use Mail::Sender;
 $sender = new Mail::Sender
  {smtp => 'mail.yourdomain.com', from => 'your@address.com'};
 $sender->MailFile({to => 'some@address.com',
  subject => 'Here is the file',
  msg => "I'm sending you the list you wanted.",
  file => 'filename.txt'});
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So the problem is that you are passing to use Mail::Sender the arguments that should go into Mail::Sender->new. When you do that, the import method of Mail::Sender which expected symbols to be imported into the caller package, tries to do that with the stringification of the hash ref you passed. And then

"HASH(0x97f5b20)" is not exported by the Mail::Sender module...
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