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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 determine_cons3rt_role_name_linux(self):
 """Determines the CONS3RT_ROLE_NAME for this Linux system, and Set the cons3rt_role_name member for this system This method determines the CONS3RT_ROLE_NAME for this system in the deployment by first checking for the environment variable, if not set, determining the value from the deployment properties. :return: None :raises: DeploymentError """

        log = logging.getLogger(self.cls_logger + '.determine_cons3rt_role_name_linux')

        # Determine IP addresses for this system
        log.info('Determining the IPv4 addresses for this system...')
        try:
            ip_addresses = get_ip_addresses()
        except CommandError:
            _, ex, trace = sys.exc_info()
            msg = 'Unable to get the IP address of this system, thus cannot determine the ' \
                  'CONS3RT_ROLE_NAME\n{e}'.format(e=str(ex))
            log.error(msg)
            raise DeploymentError, msg, trace
        else:
            log.info('Found IP addresses: {a}'.format(a=ip_addresses))

        log.info('Trying to determine IP address for eth0...')
        try:
            ip_address = ip_addresses['eth0']
        except KeyError:
            _, ex, trace = sys.exc_info()
            msg = 'Unable to determine the IP address for eth0. Found the ' \
                  'following IP addresses: {i}\n{e}'.format(i=ip_addresses,
                                                            e=str(ex))
            log.error(msg)
            raise DeploymentError, msg, trace
        else:
            log.info('Found IP address for eth0: {i}'.format(i=ip_address))

        pattern = '^cons3rt\.fap\.deployment\.machine.*0.internalIp=' + ip_address + '$'
        try:
            f = open(self.properties_file)
        except IOError:
            _, ex, trace = sys.exc_info()
            msg = 'Could not open file {f}'.format(f=self.properties_file)
            log.error(msg)
            raise DeploymentError, msg, trace
        prop_list_matched = []
        log.debug('Searching for deployment properties matching pattern: {p}'.format(p=pattern))
        for line in f:
            log.debug('Processing deployment properties file line: {l}'.format(l=line))
            if line.startswith('#'):
                continue
            elif '=' in line:
                match = re.search(pattern, line)
                if match:
                    log.debug('Found matching prop: {l}'.format(l=line))
                    prop_list_matched.append(line)
        log.debug('Number of matching properties found: {n}'.format(n=len(prop_list_matched)))
        if len(prop_list_matched) == 1:
            prop_parts = prop_list_matched[0].split('.')
            if len(prop_parts) > 5:
                self.cons3rt_role_name = prop_parts[4]
                log.info('Found CONS3RT_ROLE_NAME from deployment properties: {c}'.format(c=self.cons3rt_role_name))
                log.info('Adding CONS3RT_ROLE_NAME to the current environment...')
                os.environ['CONS3RT_ROLE_NAME'] = self.cons3rt_role_name
                return
            else:
                log.error('Property found was not formatted as expected: %s',
                          prop_parts)
        else:
            log.error('Did not find a unique matching deployment property')
        msg = 'Could not determine CONS3RT_ROLE_NAME from deployment properties'
        log.error(msg)
        raise DeploymentError(msg)