def get_upload_targets():
    """Construct and return unset dict of targets."""
    # Possible actions:
    #   normal              All available targets
    #   all_mail            All available emails
    #   [slack]{, Mail#}    Only specific emails and/or slack
    upload_targets = {'slack': False}
    for mail in range(int(get_key('Output', 'num_mail'))):
        upload_targets['mail_' + str(mail)] = False

    return upload_targets