LibreOffice Calc macro in Python to fill empty column cells to value on top

fill_unmerger_gaps.py

# This is LibreOffice Calc macro to set the values of empty cells in
# a column to the value of the first non-empty cells above the empty range.
# It is meant to be used to normalise table rows after unmerging cells
# in compound tables, thus converting them to simple tables that can then
# be algorithmically processed or exported to tabular formats such as CSV.
#
# Themacro is authored by Ahmad Gharbeia<ahmad@gharbeia.org>
# on 2020-05-19 and is licensed under GPL 3.0 license.

#from __future__ import unicode_literals
from com.sun.star.table.CellContentType import EMPTY, VALUE, TEXT, FORMULA
import uno

def range_head_filler(*args):
	desktop = XSCRIPTCONTEXT.getDesktop()
	model = desktop.getCurrentComponent()
	try:
		sheets = model.getSheets()
	except AttributeError:
		raise Exception("This script is for Calc Spreadsheets only")

	sheet = model.CurrentController.getActiveSheet()
	oArea = model.getCurrentSelection().getRangeAddress()
	first_col = oArea.StartColumn
	first_row = oArea.StartRow
	last_col = oArea.EndColumn
	last_row = oArea.EndRow

	col = first_col
	while col <= last_col:
		row = first_row
		token = ""
		while row <= last_row:
			while sheet.getCellByPosition(col, row).getType() == EMPTY:
				if token != "":
					sheet.getCellByPosition(col, row).setString(token)				
				if row == last_row:
					break
				row += 1
			else:
				token = sheet.getCellByPosition(col, row).getString()
			row += 1
		col += 1
	return None