def create_network(userid, os_version, network_info):
    """ Create network device and configure network interface.

    Input parameters:
    :userid:            USERID of the guest, last 8 if length > 8
    :os_version:        os version of the image file
    :network_info:      dict of network info
    """
    print("\nConfiguring network interface for %s ..." % userid)
    network_create_info = client.send_request('guest_create_network_interface', 
                                              userid, os_version, network_info)

    if network_create_info['overallRC']:
        raise RuntimeError("Failed to create network for guest %s!\n%s" % 
                           (userid, network_create_info))
    else:
        print("Succeeded to create network for guest %s!" % userid)