'Takes either:
A long URL string and returns shortened URL string
Or a list of long URL strings and returns a list of shortened URL strings.'

def shorten(self, longURL):

    if (not isinstance(longURL, list)):
        longURL = [longURL]
    for (index, url) in enumerate(longURL):
        if (not ('://' in url)):
            longURL[index] = ('http://' + url)
    request = self._getURL('shorten', longURL)
    result = self._fetchUrl(request)
    json = simplejson.loads(result)
    self._CheckForError(json)
    res = []
    for item in json['results'].values():
        if (item['shortKeywordUrl'] == ''):
            res.append(item['shortUrl'])
        else:
            res.append(item['shortKeywordUrl'])
    if (len(res) == 1):
        return res[0]
    else:
        return res
