Import users if I have only Email address ?

hello,

Thank you for the best newsletter plugin !

I have a list of Emails, one on each line, and I would like to import them.

The problem is that your import function seems to be looking for csv files with many columns ? But what if I have only the Email address, can it be done also ?
/wp-admin/admin.php?page=newsletter_users_import

Thank you so much for your help.