Comment 4 for bug 1572494

kde-l10nl-dutch, does not seem to be the only language pack with this problem:

A snipped of all language packs with the same problem "apt search kde-l10n":
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kde-l10n-ja/xenial,xenial 4:15.08.2-0ubuntu1 all
  ja (ja) localization for KDE

kde-l10n-kk/xenial,xenial 4:15.08.2-0ubuntu1 all
  kk (kk) localization for KDE

kde-l10n-km/xenial,xenial 4:15.08.2-0ubuntu1 all
  km (km) localization for KDE

kde-l10n-ko/xenial,xenial 4:15.08.2-0ubuntu1 all
  ko (ko) localization for KDE

kde-l10n-lt/xenial,xenial 4:15.08.2-0ubuntu1 all
  lt (lt) localization for KDE

kde-l10n-lv/xenial,xenial 4:15.08.2-0ubuntu1 all
  lv (lv) localization for KDE

kde-l10n-mr/xenial,xenial 4:15.08.2-0ubuntu1 all
  mr (mr) localization for KDE

kde-l10n-nb/xenial,xenial 4:15.08.2-0ubuntu1 all
  nb (nb) localization for KDE

kde-l10n-nds/xenial,xenial 4:15.08.2-0ubuntu1 all
  nds (nds) localization for KDE

kde-l10n-nl/xenial,xenial 4:15.08.2-0ubuntu1 all
  nl (nl) localization for KDE

kde-l10n-nn/xenial,xenial 4:15.08.2-0ubuntu1 all
  nn (nn) localization for KDE

kde-l10n-pa/xenial,xenial 4:15.08.2-0ubuntu1 all
  pa (pa) localization for KDE
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When trying to install one of these packages I encounter the same problem...