def METHOD_NAME(inventory):
    name = None
    if not inventory:
        inventory = inventory_file
    if not os.path.isfile(instance_record):
        print("ERROR: No record file found. Delete instances manually.")
        os.remove(inventory)
        print("Removed inventory file.")
        sys.exit(1)
    conn = create_connection(OS_AUTH_URL, OS_REGION_NAME,
                             OS_PROJECT_NAME, OS_USERNAME,
                             OS_PASSWORD)
    vm_list = open(instance_record, 'r').read()
    for record in vm_list.split("\n"):
        if record.strip():
            name = record.split()[0].strip()
            print("Removing Machine: {}".format(name))
            delete_server(conn, name)
        print("Removed Machine: {}".format(name))
    os.remove(instance_record)
    print("Removed record.")