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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 fetch_task_failures(self):
 """ Read in the error file from bsub """

        error_file = os.path.join(self.tmp_dir, "job.err")
        if os.path.isfile(error_file):
            with open(error_file, "r") as f_err:
                errors = f_err.readlines()
        else:
            errors = ''
        return errors