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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 qstat(jobid, context='grid'):
 """Queries status of a given job. Keyword parameters: jobid The job identifier as returned by qsub() context The setshell context in which we should try a 'qsub'. Normally you don't need to change the default. This variable can also be set to a context dictionary in which case we just setup using that context instead of probing for a new one, what can be fast. Returns a dictionary with the specific job properties """


  scmd = ['qstat', '-j', '%d' % jobid, '-f']

  logger.debug("Qstat command '%s'", ' '.join(scmd))

  from .setshell import sexec
  data = str_(sexec(context, scmd, error_on_nonzero=False))

  # some parsing:
  retval = {}
  for line in data.split('\n'):
    s = line.strip()
    if s.lower().find('do not exist') != -1: return {}
    if not s or s.find(10*'=') != -1: continue
    kv = QSTAT_FIELD_SEPARATOR.split(s, 1)
    if len(kv) == 2: retval[kv[0]] = kv[1]

  return retval