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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 _readfile(cls, filename):
 """ Reads a file a utf-8 file, and retuns character tokens. :param filename: Name of file to be read. """

        f = codecs.open(filename, encoding='utf-8')
        filedata = f.read()
        f.close()
        tokenz = LM.tokenize(filedata, mode='c')
        #print tokenz
        return tokenz