A Bark logging handler logging output via SMTP.  To specify a
    non-standard SMTP port, use the "host:port" format.  To specify
    multiple "To" addresses, separate them with commas.  To specify
    authentication credentials, supply a "username:password".

    Similar to logging.handlers.SMTPHandler.

def smtp_handler(name, logname, mailhost, fromaddr, toaddrs, subject,
                 credentials=None):
    """
    A Bark logging handler logging output via SMTP.  To specify a
    non-standard SMTP port, use the "host:port" format.  To specify
    multiple "To" addresses, separate them with commas.  To specify
    authentication credentials, supply a "username:password".

    Similar to logging.handlers.SMTPHandler.
    """

    return wrap_log_handler(logging.handlers.SMTPHandler(
        mailhost, fromaddr, toaddrs, subject, credentials=credentials))