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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 log_tail(self, nlines=10):
 """ Return the last ``nlines`` lines of the log file """

        log_path = os.path.join(self.working_dir, self.log_name)
        with open(log_path) as fp:
            d = collections.deque(maxlen=nlines)
            d.extend(fp)
            return ''.join(d)