Traceback производят при добавлении репозитория

Каждый раз, когда я добавляю репозиторий с помощью add-apt-repository команда, Traceback называют относительно файлов /usr/bin/lsb_release и /usr/lib/python3/dist-packages/lsb_release.py

(Я использую Ubuntu 16.04.1),

Вывод следующий при добавлении репозитория:

Traceback (most recent call last):
  File "/usr/bin/lsb_release", line 98, in <module>
    main()
  File "/usr/bin/lsb_release", line 62, in main
    distinfo = lsb_release.get_distro_information(options.upstream)
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 344, in get_distro_information
    distinfo = guess_debian_release()
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 239, in guess_debian_release
    get_distro_info(distinfo['ID'])
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in get_distro_info
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in <lambda>
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
ValueError: could not convert string to float: '6.06 LTS'
Traceback (most recent call last):
  File "/usr/bin/lsb_release", line 98, in <module>
    main()
  File "/usr/bin/lsb_release", line 62, in main
    distinfo = lsb_release.get_distro_information(options.upstream)
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 344, in get_distro_information
    distinfo = guess_debian_release()
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 239, in guess_debian_release
    get_distro_info(distinfo['ID'])
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in get_distro_info
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in <lambda>
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
ValueError: could not convert string to float: '12.04 LTS'
Traceback (most recent call last):
  File "/usr/bin/lsb_release", line 98, in <module>
    main()
  File "/usr/bin/lsb_release", line 62, in main
    distinfo = lsb_release.get_distro_information(options.upstream)
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 344, in get_distro_information
    distinfo = guess_debian_release()
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 239, in guess_debian_release
    get_distro_info(distinfo['ID'])
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in get_distro_info
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
  File "/usr/lib/python3/dist-packages/lsb_release.py", line 41, in <lambda>
    RELEASES_ORDER.sort(key=lambda n: float(n[0]))
ValueError: could not convert string to float: '12.04 LTS'

Когда я удаляю /usr/bin/lsb_release, Я не получаю это traceback, но в моем системном лотке красный значок, как показывают, сообщает мне, что была ошибка при получении обновлений.

Заранее спасибо.