Hi!
Im trying to export a selection of svg paths. The expoted svg is to be used with a laser cutter so i want to add a path effect offset to take the kerf into account.
The problem is that i cant  bake in the path effect to  'd' .

here is the code i have so far:

# -*- coding: utf-8 -*-
"""
Created on Fri Jan 20 20:56:49 2023

@author: Erik
"""


from inkex import EffectExtension, PathEffect, errormsg
import inkex
from lxml import etree
import os
from copy import deepcopy
class OffsetAndExport(EffectExtension):
    def add_arguments(self, pars):
        pars.add_argument("--offset", type=str)


    def effect(self):
        paths_element= []
        for element in self.svg.selection:
            if element.TAG == 'path':
                paths_element.append(element)

        
        if not paths_element:
            errormsg("Please select at least one path" )



        offset = self.options.offset
        offset_param_dict = {"update_on_knot_move": "true", 
                                  "attempt_force_join": "false", 
                                  "miter_limit": "4", 
                                  "offset": offset, 
                                  "unit": "mm",
                                  "linejoin_type": "round",
                                  "lpeversion": "1.2",
                                  "is_visible": "true",
                                  "effect": "offset"}
        


        for p in paths_element:
            effect = PathEffect()
            for key in offset_param_dict:
                effect.set(key, offset_param_dict[key])          

            self.svg.defs.add(effect)
            p.set('inkscape:original-d', p.attrib["d"])
            p.set('inkscape:path-effect', effect.get_id(as_url = 1))
            #p.pop('d')


        # Create a new SVG document
        new_svg = etree.Element('svg', nsmap=self.svg.nsmap)
        for element in self.svg.selection:
            if element.tag == inkex.addNS('path', 'svg'):
                new_element = deepcopy(element)
                new_svg.append(new_element)


        # Output the new SVG document
        output_svg = etree.tostring(new_svg, pretty_print=True, xml_declaration=True, encoding='UTF-8')

        #set  file name as the parent group id:
        file_name = element.getparent().get('id')
    
        with open(file_name + '.svg', 'wb') as f:
            f.write(output_svg)
            




if __name__ == '__main__':
    OffsetAndExport().run()

<?xml version="1.0" encoding="UTF-8"?>
<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
  <name>Export selected with offset</name>
  <id>org.inkscape.marquentry.Export_selected</id>
  <param name="offset" type="string" gui-text="Offset (kerf devided by two ):">name</param>
  <effect>
    <effects-menu>
      <submenu name="Marquetry"/>
    </effects-menu>
  </effect>
  <script>
    <command location="inx" interpreter="python">export_selected_paths_with_kerf_offset.py</command>
  </script>
</inkscape-extension>

To bake in `Path Effects` needs a command call to `object-to-path`

ok, thanks!