How to use the redfish.rest.v1_helper.ServerDownOrUnreachableError function in redfish

iLO_account = "None"
    iLO_password = "None"

    # When running remotely connect using the iLO secured (https://) address, 
    # iLO account name, and password to send https requests
    # iLO_https_url acceptable examples:
    # "https://10.0.0.100"
    # "https://f250asha.americas.hpqcorp.net"
    # iLO_https_url = "https://10.0.0.100"
    # iLO_account = "admin"
    # iLO_password = "password"

    # Create a REDFISH object
    try:
        REDFISH_OBJ = RedfishObject(iLO_https_url, iLO_account, iLO_password)
    except ServerDownOrUnreachableError, excp:
        sys.stderr.write("ERROR: server not reachable or doesn't support " \
                                                                "RedFish.\n")
        sys.exit()
    except Exception, excp:
        raise excp
    ex52_get_ilo_ip(REDFISH_OBJ)

# iLO_account = "None"
    # iLO_password = "None"

    # When running remotely connect using the iLO secured (https://) address, 
    # iLO account name, and password to send https requests
    # iLO_https_url acceptable examples:
    # "https://10.0.0.100"
    # "https://f250asha.americas.hpqcorp.net"
    iLO_https_url = "https://10.0.0.100"
    iLO_account = "admin"
    iLO_password = "password"

    # Create a REDFISH object
    try:
        REDFISH_OBJ = RedfishObject(iLO_https_url, iLO_account, iLO_password)
    except ServerDownOrUnreachableError, excp:
        sys.stderr.write("ERROR: server not reachable or doesn't support " \
                                                                "RedFish.\n")
        sys.exit()
    except Exception, excp:
        raise excp

    ex53_update_ilo_firmware(REDFISH_OBJ, "http://test.com/ilo4_244.bin", False)

# iLO_account = "None"
    # iLO_password = "None"

    # When running remotely connect using the iLO secured (https://) address, 
    # iLO account name, and password to send https requests
    # iLO_https_url acceptable examples:
    # "https://10.0.0.100"
    # "https://f250asha.americas.hpqcorp.net"
    iLO_https_url = "https://10.0.0.100"
    iLO_account = "admin"
    iLO_password = "password"

    # Create a REDFISH object
    try:
        REDFISH_OBJ = RedfishObject(iLO_https_url, iLO_account, iLO_password)
    except ServerDownOrUnreachableError, excp:
        sys.stderr.write("ERROR: server not reachable or doesn't support " \
                                                                "RedFish.\n")
        sys.exit()
    except Exception, excp:
        raise excp

    ex50_get_csr(REDFISH_OBJ, "csr.txt")

# iLO_account = "None"
    # iLO_password = "None"

    # When running remotely connect using the iLO secured (https://) address, 
    # iLO account name, and password to send https requests
    # iLO_https_url acceptable examples:
    # "https://10.0.0.100"
    # "https://f250asha.americas.hpqcorp.net"
    iLO_https_url = "https://10.0.0.100"
    iLO_account = "admin"
    iLO_password = "password"

    # Create a REDFISH object
    try:
        REDFISH_OBJ = RedfishObject(iLO_https_url, iLO_account, iLO_password)
    except ServerDownOrUnreachableError, excp:
        sys.stderr.write("ERROR: server not reachable or doesn't support " \
                                                                "RedFish.\n")
        sys.exit()
    except Exception, excp:
        raise excp

    ex51_import_ssl(REDFISH_OBJ, "ssl.txt")

# iLO_account = "None"
    # iLO_password = "None"

    # When running remotely connect using the iLO secured (https://) address, 
    # iLO account name, and password to send https requests
    # iLO_https_url acceptable examples:
    # "https://10.0.0.100"
    # "https://f250asha.americas.hpqcorp.net"
    iLO_https_url = "https://10.0.0.100"
    iLO_account = "admin"
    iLO_password = "password"

    # Create a REDFISH object
    try:
        REDFISH_OBJ = RedfishObject(iLO_https_url, iLO_account, iLO_password)
    except ServerDownOrUnreachableError, excp:
        sys.stderr.write("ERROR: server not reachable or doesn't support " \
                                                                "RedFish.\n")
        sys.exit()
    except Exception, excp:
        raise excp

    ex49_generate_csr(REDFISH_OBJ, {"City" : "City",\
                                    "CommonName": "Common Name",\
                                    "Country": "US",\
                                    "OrgName": "Organization",\
                                    "OrgUnit": "Unit",\
                                    "State": "State"})