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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 get_supported_boot_mode(self):
 """Get the system supported boot modes. :return: any one of the following proliantutils.ilo.constants: SUPPORTED_BOOT_MODE_LEGACY_BIOS_ONLY, SUPPORTED_BOOT_MODE_UEFI_ONLY, SUPPORTED_BOOT_MODE_LEGACY_BIOS_AND_UEFI :raises: IloError, if account not found or on an error from iLO. """

        sushy_system = self._get_sushy_system(PROLIANT_SYSTEM_ID)
        try:
            return SUPPORTED_BOOT_MODE_MAP.get(
                sushy_system.supported_boot_mode)
        except sushy.exceptions.SushyError as e:
            msg = (self._('The Redfish controller failed to get the '
                          'supported boot modes. Error: %s') % e)
            LOG.debug(msg)
            raise exception.IloError(msg)