既存のPDF ファイルに 矩形の白塗りをする方法です。
blank_pdf.py
#! /usr/bin/python
#
# blank_pdf.py
#
# Mar/26/2023
#
# ------------------------------------------------------------------
import sys
from pdfrw import PdfReader
from pdfrw.buildxobj import pagexobj
from pdfrw.toreportlab import makerl
from reportlab.pdfgen import canvas
import reportlab.lib.colors as color
# ------------------------------------------------------------------
def blank_square_proc(pdf_canvas,xx,yy,width,height):
pdf_canvas.setFillColor(color.white)
pdf_canvas.rect(xx, yy, width, height,stroke=False, fill=True)
# ------------------------------------------------------------------
def blank_proc(pdf_canvas):
#
blank_square_proc(pdf_canvas,10,10,600,180)
#
# ------------------------------------------------------------------
sys.stderr.write("*** 開始 ***\n")
file_in = sys.argv[1]
file_out = sys.argv[2]
sys.stderr.write(file_in + "\n")
sys.stderr.write(file_out + "\n")
#
pdf_canvas = canvas.Canvas(file_out)
pdf_obj = PdfReader(file_in,decompress=False)
page = pdf_obj.pages
pp = pagexobj(page[0])
pdf_canvas.doForm(makerl(pdf_canvas, pp))
blank_proc(pdf_canvas)
pdf_canvas.showPage()
pdf_canvas.save()
#
sys.stderr.write("*** 終了 ***\n")
# ------------------------------------------------------------------
実行方法
./blank_pdf.py in01.pdf out01.pdf
確認したバージョン
$ python --version
Python 3.10.10