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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_name(key):
 """Find the English name for the language specified by key. u'Breton' u'Swahili' """

    item = find(whatever=key)
    if not item:
        raise NonExistentLanguageError('Language does not exist.')
    return item[u'name']