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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 guess_server_name():
 """We often use the same servers, which one are we running on now ?"""

    if   os.environ.get('CSCSERVICE')          == 'sisu':         return "sisu"
    elif os.environ.get('SLURM_JOB_PARTITION') == 'halvan':       return "halvan"
    elif os.environ.get('SNIC_RESOURCE')       == 'milou':        return "milou"
    elif os.environ.get('LAPTOP')              == 'macbook_air':  return "macbook_air"
    else:                                                         return "unknown"