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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 _Ifup(self, interfaces, logger):
 """Activate network interfaces. Args: interfaces: list of string, the output device names to enable. logger: logger object, used to write to SysLog and serial port. """

    ifup = ['/usr/sbin/wicked', 'ifup', '--timeout', '1']
    try:
      subprocess.check_call(ifup + interfaces)
    except subprocess.CalledProcessError:
      logger.warning('Could not activate interfaces %s.', interfaces)