1. run  
         python3 yang_rfc.py ./bgp/ (generate yang_modules file) or
         python3 yang_rfc.py  (If there are yang_modules file in the directory)   
 2. out
 Choice Modeule Name: ['ietf-netconf', 'openconfig-bgp-policy', 'openconfig-inet-types', 'openconfig-bgp-types', 'openconfig-policy-types', 'openconfig-types', 'openconfig-yang-types', 'ietf-inet-types', 'ietf-yang-types', 'ietf-interfaces', 'openconfig-interfaces', 'openconfig-extensions', 'openconfig-bgp', 'openconfig-routing-policy']
module >openconfig-bgp
 (yang contianer,list,leaf,leaf-list,... tree)
 openconfig-bgp>*
 
 
 3、openconfig-bgp>*
.......
.......
                ├ container use-multiple-paths ->-6438312242391315966
                    ├ container config ->4874438011303423425
                        ├ leaf enabled ->-8644924308082446906
                    ├ container state
                        ├ config false
                        ├ leaf enabled
                    ├ container ebgp ->-73683027755021457
                        ├ container config ->6271267819966798184
                            ├ leaf allow-multiple-as ->201404358886246952
                            ├ leaf maximum-paths ->-7024144332218161246
                        ├ container state
                            ├ config false
                            ├ leaf allow-multiple-as
                            ├ leaf maximum-paths
                    ├ container ibgp ->-2251363372557777736
                        ├ container config ->2237497577408369645
                            ├ leaf maximum-paths ->8891077290169949704
                        ├ container state
                            ├ config false
                            ├ leaf maximum-paths
                ├ container apply-policy ->-3688259472857241272
                    ├ container config ->-542825605681862353
                        ├ leaf-list import-policy ->202389048834029177
                        ├ leaf default-import-policy ->1581993182980904389
                        ├ leaf-list export-policy ->-2822994043534005579
                        ├ leaf default-export-policy ->8128682493600742992
                    ├ container state
                        ├ config false
                        ├ leaf-list import-policy
                        ├ leaf default-import-policy
                        ├ leaf-list export-policy
                        ├ leaf default-export-policy
......
(copy paste -3688259472857241272)
openconfig-bgp>-3688259472857241272         
/openconfig-bgp>-3688259472857241272

├ container apply-policy ->-3688259472857241272
    ├ container config ->-542825605681862353
        ├ leaf-list import-policy(path /openconfig-routing-policy:routing-policy/openconfig-routing-policy:policy-definitions/openconfig-routing-policy:policy-definition/openconfig-routing-policy:name) ->202389048834029177
            ├ path_point (/openconfig-routing-policy:routing-policy/openconfig-routing-policy:policy-definitions/openconfig-routing-policy:policy-definition[{}]/openconfig-routing-policy:config/openconfig-routing-policy:name)
                ├ type string
            ├ ordered-by user
        ├ leaf default-import-policy ->1581993182980904389
            ├ type default-policy-type
                ├ type enumeration
                    ├ enum ACCEPT_ROUTE
                    ├ enum REJECT_ROUTE
            ├ default REJECT_ROUTE
        ├ leaf-list export-policy(path /openconfig-routing-policy:routing-policy/openconfig-routing-policy:policy-definitions/openconfig-routing-policy:policy-definition/openconfig-routing-policy:name) ->-2822994043534005579
            ├ path_point (/openconfig-routing-policy:routing-policy/openconfig-routing-policy:policy-definitions/openconfig-routing-policy:policy-definition[{}]/openconfig-routing-policy:config/openconfig-routing-policy:name)
                ├ type string
            ├ ordered-by user
        ├ leaf default-export-policy ->8128682493600742992
            ├ type default-policy-type
                ├ type enumeration
                    ├ enum ACCEPT_ROUTE
                    ├ enum REJECT_ROUTE
            ├ default REJECT_ROUTE

<Node>:
  oc-bgp:bgp/oc-bgp:peer-groups/oc-bgp:peer-group[{}]/oc-bgp:apply-policy
<SubNode>:
  oc-bgp:config/oc-bgp:import-policy[{}]
  oc-bgp:config/oc-bgp:default-import-policy
  oc-bgp:config/oc-bgp:export-policy[{}]
  oc-bgp:config/oc-bgp:default-export-policy
/openconfig-bgp>
([{}] is list or leaf-list)

4、input namespaces
/openconfig-bgp>namespaces 
Show Module Prefix :
['openconfig-bgp']
Namespaces in yang module :
{'openconfig-bgp': 'http://openconfig.net/yang/bgp'}
Module name to prefix :
{'openconfig-bgp': 'oc-bgp'}
Add namespace yang nc if need :
{'yang':'urn:ietf:params:xml:ns:yang:ietf-yang-types','nc':'urn:ietf:params:xml:ns:netconf:base:1.0'}


5、now use xpath2xml build xml  (wangke1970/xpath2xml)
#example                         
from xpath2xml import xpath2xml
ns = {'yang':'urn:ietf:params:xml:ns:yang:ietf-yang-types','nc':'urn:ietf:params:xml:ns:netconf:base:1.0','oc-bgp':'http://openconfig.net/yang/bgp'}
bgp_x = xpath2xml(ns,'nc:rpc')
example_str_1 = 'nc:edit-config/nc:config/' + 'oc-bgp:bgp/oc-bgp:peer-groups/oc-bgp:peer-group[0]/oc-bgp:apply-policy/oc-bgp:config'
example_str_2 = 'nc:edit-config/nc:config/' + 'oc-bgp:bgp/oc-bgp:peer-groups/oc-bgp:peer-group[1]/oc-bgp:apply-policy/oc-bgp:config'

bgp_x.add(example_str_1)
bgp_x.add(example_str_2)
#注意 oc-bgp:default-import-policy','oc-bgp:export-policy[0]','oc-bgp:export-policy[1]','oc-bgp:default-export-policy' 次序先入的node先生成xml 
bgp_x.insert(example_str_1,'oc-bgp:import-policy[0]')
bgp_x.insert(example_str_1,'oc-bgp:import-policy[1]')

bgp_x.inserts(example_str_1,['oc-bgp:default-import-policy','oc-bgp:export-policy[0]','oc-bgp:export-policy[1]','oc-bgp:default-export-policy'])
bgp_x.insert(example_str_2,'oc-bgp:import-policy[0]')
bgp_x.inserts(example_str_2,['oc-bgp:default-import-policy','oc-bgp:export-policy[0]','oc-bgp:default-export-policy'])
print(bgp_x.xml)
tree = bgp_x.tree
ss = tree.dump
print(ss)
######################out############################
<?xml version='1.0' encoding='utf-8'?>
<nc:rpc xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0" xmlns:oc-bgp="http://openconfig.net/yang/bgp"><nc:edit-config><nc:config><oc-bgp:bgp><oc-bgp:peer-groups><oc-bgp:peer-group><oc-bgp:apply-policy><oc-bgp:config><oc-bgp:import-policy /><oc-bgp:import-policy /><oc-bgp:default-import-policy /><oc-bgp:export-policy /><oc-bgp:export-policy /><oc-bgp:default-export-policy /></oc-bgp:config></oc-bgp:apply-policy></oc-bgp:peer-group><oc-bgp:peer-group><oc-bgp:apply-policy><oc-bgp:config><oc-bgp:import-policy /><oc-bgp:default-import-policy /><oc-bgp:export-policy /><oc-bgp:default-export-policy /></oc-bgp:config></oc-bgp:apply-policy></oc-bgp:peer-group></oc-bgp:peer-groups></oc-bgp:bgp></nc:config></nc:edit-config></nc:rpc>
nc:rpc
 ├ nc:edit-config
     ├ nc:config
         ├ oc-bgp:bgp
             ├ oc-bgp:peer-groups
                 ├ oc-bgp:peer-group[0]
                     ├ oc-bgp:apply-policy
                         ├ oc-bgp:config
                             ├ oc-bgp:import-policy[0]
                             ├ oc-bgp:import-policy[1]
                             ├ oc-bgp:default-import-policy
                             ├ oc-bgp:export-policy[0]
                             ├ oc-bgp:export-policy[1]
                             ├ oc-bgp:default-export-policy
                 ├ oc-bgp:peer-group[1]
                     ├ oc-bgp:apply-policy
                         ├ oc-bgp:config
                             ├ oc-bgp:import-policy
                             ├ oc-bgp:default-import-policy
                             ├ oc-bgp:export-policy
                             ├ oc-bgp:default-export-policy

6、find node
/huawei-mac>find(container global-attribute)
H:-5640491272284131244 ➔ P:/huawei-mac:mac/huawei-mac:global-attribute
/huawei-mac>