diff --git a/src/conf_mode/protocols_ospf.py b/src/conf_mode/protocols_ospf.py
index cddd3765e..2f07142a3 100755
--- a/src/conf_mode/protocols_ospf.py
+++ b/src/conf_mode/protocols_ospf.py
@@ -1,270 +1,268 @@
 #!/usr/bin/env python3
 #
 # Copyright (C) 2021-2023 VyOS maintainers and contributors
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 or later as
 # published by the Free Software Foundation.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
-
 from sys import exit
 from sys import argv
 
 from vyos.config import Config
 from vyos.config import config_dict_merge
 from vyos.configdict import dict_merge
 from vyos.configdict import node_changed
 from vyos.configverify import verify_common_route_maps
 from vyos.configverify import verify_route_map
 from vyos.configverify import verify_interface_exists
 from vyos.configverify import verify_access_list
 from vyos.template import render_to_string
 from vyos.utils.dict import dict_search
 from vyos.utils.network import get_interface_config
 from vyos import ConfigError
 from vyos import frr
 from vyos import airbag
 airbag.enable()
 
 def get_config(config=None):
     if config:
         conf = config
     else:
         conf = Config()
 
     vrf = None
     if len(argv) > 1:
         vrf = argv[1]
 
     base_path = ['protocols', 'ospf']
 
     # eqivalent of the C foo ? 'a' : 'b' statement
     base = vrf and ['vrf', 'name', vrf, 'protocols', 'ospf'] or base_path
     ospf = conf.get_config_dict(base, key_mangling=('-', '_'),
                                 get_first_key=True)
 
     # Assign the name of our VRF context. This MUST be done before the return
     # statement below, else on deletion we will delete the default instance
     # instead of the VRF instance.
     if vrf: ospf['vrf'] = vrf
 
     # FRR has VRF support for different routing daemons. As interfaces belong
     # to VRFs - or the global VRF, we need to check for changed interfaces so
     # that they will be properly rendered for the FRR config. Also this eases
     # removal of interfaces from the running configuration.
     interfaces_removed = node_changed(conf, base + ['interface'])
     if interfaces_removed:
         ospf['interface_removed'] = list(interfaces_removed)
 
     # Bail out early if configuration tree does no longer exist. this must
     # be done after retrieving the list of interfaces to be removed.
     if not conf.exists(base):
         ospf.update({'deleted' : ''})
         return ospf
 
     # We have gathered the dict representation of the CLI, but there are default
     # options which we need to update into the dictionary retrived.
     default_values = conf.get_config_defaults(**ospf.kwargs, recursive=True)
 
     # We have to cleanup the default dict, as default values could enable features
     # which are not explicitly enabled on the CLI. Example: default-information
     # originate comes with a default metric-type of 2, which will enable the
     # entire default-information originate tree, even when not set via CLI so we
     # need to check this first and probably drop that key.
     if dict_search('default_information.originate', ospf) is None:
         del default_values['default_information']
     if 'mpls_te' not in ospf:
         del default_values['mpls_te']
     if 'graceful_restart' not in ospf:
         del default_values['graceful_restart']
     for area_num in default_values.get('area', []):
         if dict_search(f'area.{area_num}.area_type.nssa', ospf) is None:
             del default_values['area'][area_num]['area_type']['nssa']
 
     for protocol in ['babel', 'bgp', 'connected', 'isis', 'kernel', 'rip', 'static']:
         if dict_search(f'redistribute.{protocol}', ospf) is None:
             del default_values['redistribute'][protocol]
 
     for interface in ospf.get('interface', []):
         # We need to reload the defaults on every pass b/c of
         # hello-multiplier dependency on dead-interval
         # If hello-multiplier is set, we need to remove the default from
         # dead-interval.
         if 'hello_multiplier' in ospf['interface'][interface]:
             del default_values['interface'][interface]['dead_interval']
 
     ospf = config_dict_merge(default_values, ospf)
 
     # We also need some additional information from the config, prefix-lists
     # and route-maps for instance. They will be used in verify().
     #
     # XXX: one MUST always call this without the key_mangling() option! See
     # vyos.configverify.verify_common_route_maps() for more information.
     tmp = conf.get_config_dict(['policy'])
     # Merge policy dict into "regular" config dict
     ospf = dict_merge(tmp, ospf)
 
     return ospf
 
 def verify(ospf):
     if not ospf:
         return None
 
     verify_common_route_maps(ospf)
 
     # As we can have a default-information route-map, we need to validate it!
     route_map_name = dict_search('default_information.originate.route_map', ospf)
     if route_map_name: verify_route_map(route_map_name, ospf)
 
     # Validate if configured Access-list exists
     if 'area' in ospf:
           for area, area_config in ospf['area'].items():
               if 'import_list' in area_config:
                   acl_import = area_config['import_list']
                   if acl_import: verify_access_list(acl_import, ospf)
               if 'export_list' in area_config:
                   acl_export = area_config['export_list']
                   if acl_export: verify_access_list(acl_export, ospf)
 
     if 'interface' in ospf:
         for interface, interface_config in ospf['interface'].items():
             verify_interface_exists(interface)
             # One can not use dead-interval and hello-multiplier at the same
             # time. FRR will only activate the last option set via CLI.
             if {'hello_multiplier', 'dead_interval'} <= set(interface_config):
                 raise ConfigError(f'Can not use hello-multiplier and dead-interval ' \
                                   f'concurrently for {interface}!')
 
             # One can not use the "network <prefix> area <id>" command and an
             # per interface area assignment at the same time. FRR will error
             # out using: "Please remove all network commands first."
             if 'area' in ospf and 'area' in interface_config:
                 for area, area_config in ospf['area'].items():
                     if 'network' in area_config:
                         raise ConfigError('Can not use OSPF interface area and area ' \
                                           'network configuration at the same time!')
 
             # If interface specific options are set, we must ensure that the
             # interface is bound to our requesting VRF. Due to the VyOS
             # priorities the interface is bound to the VRF after creation of
             # the VRF itself, and before any routing protocol is configured.
             if 'vrf' in ospf:
                 vrf = ospf['vrf']
                 tmp = get_interface_config(interface)
                 if 'master' not in tmp or tmp['master'] != vrf:
                     raise ConfigError(f'Interface "{interface}" is not a member of VRF "{vrf}"!')
 
     # Segment routing checks
     if dict_search('segment_routing.global_block', ospf):
         g_high_label_value = dict_search('segment_routing.global_block.high_label_value', ospf)
         g_low_label_value = dict_search('segment_routing.global_block.low_label_value', ospf)
 
         # If segment routing global block high or low value is blank, throw error
         if not (g_low_label_value or g_high_label_value):
             raise ConfigError('Segment routing global-block requires both low and high value!')
 
         # If segment routing global block low value is higher than the high value, throw error
         if int(g_low_label_value) > int(g_high_label_value):
             raise ConfigError('Segment routing global-block low value must be lower than high value')
 
     if dict_search('segment_routing.local_block', ospf):
         if dict_search('segment_routing.global_block', ospf) == None:
             raise ConfigError('Segment routing local-block requires global-block to be configured!')
 
         l_high_label_value = dict_search('segment_routing.local_block.high_label_value', ospf)
         l_low_label_value = dict_search('segment_routing.local_block.low_label_value', ospf)
 
         # If segment routing local-block high or low value is blank, throw error
         if not (l_low_label_value or l_high_label_value):
             raise ConfigError('Segment routing local-block requires both high and low value!')
 
         # If segment routing local-block low value is higher than the high value, throw error
         if int(l_low_label_value) > int(l_high_label_value):
             raise ConfigError('Segment routing local-block low value must be lower than high value')
 
         # local-block most live outside global block
         global_range = range(int(g_low_label_value), int(g_high_label_value) +1)
         local_range  = range(int(l_low_label_value), int(l_high_label_value) +1)
 
         # Check for overlapping ranges
         if list(set(global_range) & set(local_range)):
             raise ConfigError(f'Segment-Routing Global Block ({g_low_label_value}/{g_high_label_value}) '\
                               f'conflicts with Local Block ({l_low_label_value}/{l_high_label_value})!')
 
     # Check for a blank or invalid value per prefix
     if dict_search('segment_routing.prefix', ospf):
         for prefix, prefix_config in ospf['segment_routing']['prefix'].items():
             if 'index' in prefix_config:
                 if prefix_config['index'].get('value') is None:
                     raise ConfigError(f'Segment routing prefix {prefix} index value cannot be blank.')
 
     # Check for explicit-null and no-php-flag configured at the same time per prefix
     if dict_search('segment_routing.prefix', ospf):
         for prefix, prefix_config in ospf['segment_routing']['prefix'].items():
             if 'index' in prefix_config:
                 if ("explicit_null" in prefix_config['index']) and ("no_php_flag" in prefix_config['index']):
                     raise ConfigError(f'Segment routing prefix {prefix} cannot have both explicit-null '\
                                       f'and no-php-flag configured at the same time.')
 
     # Check route summarisation
     if 'summary_address' in ospf:
         for prefix, prefix_options in ospf['summary_address'].items():
             if {'tag', 'no_advertise'} <= set(prefix_options):
                 raise ConfigError(f'Can not set both "tag" and "no-advertise" for Type-5 '\
                                   f'and Type-7 route summarisation of "{prefix}"!')
 
     return None
 
 def generate(ospf):
     if not ospf or 'deleted' in ospf:
         return None
 
     ospf['frr_ospfd_config'] = render_to_string('frr/ospfd.frr.j2', ospf)
     return None
 
 def apply(ospf):
     ospf_daemon = 'ospfd'
 
     # Save original configuration prior to starting any commit actions
     frr_cfg = frr.FRRConfig()
 
     # Generate empty helper string which can be ammended to FRR commands, it
     # will be either empty (default VRF) or contain the "vrf <name" statement
     vrf = ''
     if 'vrf' in ospf:
         vrf = ' vrf ' + ospf['vrf']
 
     frr_cfg.load_configuration(ospf_daemon)
     frr_cfg.modify_section(f'^router ospf{vrf}', stop_pattern='^exit', remove_stop_mark=True)
 
     for key in ['interface', 'interface_removed']:
         if key not in ospf:
             continue
         for interface in ospf[key]:
             frr_cfg.modify_section(f'^interface {interface}', stop_pattern='^exit', remove_stop_mark=True)
 
     if 'frr_ospfd_config' in ospf:
         frr_cfg.add_before(frr.default_add_before, ospf['frr_ospfd_config'])
 
     frr_cfg.commit_configuration(ospf_daemon)
 
     return None
 
 if __name__ == '__main__':
     try:
         c = get_config()
         verify(c)
         generate(c)
         apply(c)
     except ConfigError as e:
         print(e)
         exit(1)