<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def finished(cls, jobid):
 """Check whether a SLURM job is finished or not"""

        output = subprocess.check_output(
            [SACCT, '-n', '-X', '-o', "end", '-j', str(jobid)]
        )
        end = output.strip().decode()
        return end not in {'Unknown', ''}