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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 CallHwclock(logger):
 """Sync clock using hwclock. Args: logger: logger object, used to write to SysLog and serial port. """

  command = ['/sbin/hwclock', '--hctosys']
  try:
    subprocess.check_call(command)
  except subprocess.CalledProcessError:
    logger.warning('Failed to sync system time with hardware clock.')
  else:
    logger.info('Synced system time with hardware clock.')