Long-running backup fails by timeout about imapbackup HOT 4 CLOSED

Usage: imapbackup [OPTIONS] -s HOST -u USERNAME [-p PASSWORD]
 -a --append-to-mboxes     Append new messages to mbox files. (default)
 -y --yes-overwrite-mboxes Overwite existing mbox files instead of appending.
 -n --compress=none        Use one plain mbox file for each folder. (default)
 -z --compress=gzip        Use mbox.gz files.  Appending may be very slow.
 -b --compress=bzip2       Use mbox.bz2 files. Appending not supported: use -y.
 -f --=folder              Specifify which folders use.  Comma separated list.
 -e --ssl                  Use SSL.  Port defaults to 993.
 -k KEY --key=KEY          PEM private key file for SSL.  Specify cert, too.
 -c CERT --cert=CERT       PEM certificate chain for SSL.  Specify key, too.
                           Python's SSL module doesn't check the cert chain.
 -s HOST --server=HOST     Address of server, port optional, eg. mail.com:143
 -u USER --user=USER       Username to log into server
 -p PASS --pass=PASS       Prompts for password if not specified.
 -t SECS --timeout=SECS    Sets socket timeout to SECS seconds.
 --thunderbird             Create Mozilla Thunderbird compatible mailbox
 --nospinner               Disable spinner (makes output log-friendly)

NOTE: mbox files are created in the current working directory.

Traceback (most recent call last):
  File "imapbackup.py", line 713, in <module>
    main()
  File "imapbackup.py", line 600, in main
    server = connect_and_login(config)
  File "imapbackup.py", line 547, in connect_and_login
    if config['timeout']:
KeyError: 'timeout