Need help with small edit to a plug-in

Code:
#!/usr/bin/env python



# center_resize_all_layers_to_image_size.py

# Created by Tin Tran http://gimplearn.net

# License: GPLv3

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# 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.

#

# To view a copy of the GNU General Public License

# visit: http://www.gnu.org/licenses/gpl.html

#

#

# ------------

#| Change Log |

# ------------

# Rel 1: Initial release.

#import string

#import Image

import random

from gimpfu import *

import math

#from array import array

#import sys

    

def python_tt_center_resize_all_layers_to_image_size(image, layer):

    #convert to index mode

    # pdb.gimp_image_convert_indexed(image,CONVERT_DITHER_NONE,CONVERT_PALETTE_GENERATE,colors,FALSE,TRUE,'ignored')

    # num_bytes,colormap = pdb.gimp_image_get_colormap(image);

    # num_bytes_per_color = len(colormap)/colors

    # pdb.gimp_image_convert_rgb(image) #convert it back to RGB

    non_empty,x1,y1,x2,y2 = pdb.gimp_selection_bounds(image)

    if (non_empty == TRUE):

        width = x2-x1

        height = y2-y1

        for l in image.layers:

            pdb.gimp_layer_scale(l,width,height,TRUE)

            pdb.gimp_layer_set_offsets(l,x1,y1)

    else:    

        for l in image.layers:

            pdb.gimp_layer_scale(l,image.width,image.height,TRUE)

            pdb.gimp_layer_set_offsets(l,0,0)



register(

    "python_fu_tt_center_resize_all_layers_to_image_size",                           

    "Center Resize All Layers To Image Size",

    "Center Resize All Layers To Image Size",

    "Tin Tran",

    "Tin Tran",

    "August 2020",

    "<Image>/Python-Fu/Center Resize All Layers To Image Size",             #Menu path

    "RGB*, GRAY*", 

    [

    # (PF_SPINNER, "width", "Width:", 2000, (10, 3000, 10)),

    # (PF_SPINNER, "height", "Height:", 2500, (10, 3000, 10)),

    ],

    [],

    python_tt_center_resize_all_layers_to_image_size)



main()