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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 _exec_ipmitool(driver_info, command):
 """Execute the ipmitool command. This uses the lanplus interface to communicate with the BMC device driver. :param driver_info: the ipmitool parameters for accessing a node. :param command: the ipmitool command to be executed. """

    ipmi_cmd = ("ipmitool -H %(address)s"
                " -I lanplus -U %(user)s -P %(passwd)s %(cmd)s"
                % {'address': driver_info['address'],
                   'user': driver_info['username'],
                   'passwd': driver_info['password'],
                   'cmd': command})

    out = None
    try:
        out = subprocess.check_output(ipmi_cmd, shell=True)
    except Exception:
        pass
    return out