def disable(cls, session, id_):
""" Disable the language 'id_'
if it is not the only enabled one,
then delete all translations for that language.
"""
if Language.count(session, cls.enabled == True) < 2:
raise QuotaError('Cannot disable last enabled language.')
language = Language.get(session, id_)
language.enabled = False
NodeInfo.remove_translations(session, id_)
return language
