':return: the given file(s) as a list of the text content of Tweets as
as a list of words, screenanames, hashtags, URLs and punctuation symbols.
:rtype: list(list(str))'

def tokenized(self, fileids=None):

    tweets = self.strings(fileids)
    tokenizer = self._word_tokenizer
    return [tokenizer.tokenize(t) for t in tweets]
