[Python] ModuleNotFoundError: No module named 'reportlab' after ModuleNotFoundError: No module...

I have made a python script with several imports at the beginning:

from flask import render_template, request, send_file
from reportlab.lib.pagesizes import A4
from reportlab.pdfgen import canvas
from reportlab.graphics.barcode import code128
from reportlab.lib.units import mm
import io
import webbrowser


After compiling the script to a .exe file keep getting the error:

File "app2.py", line 7, in <module>
ModuleNotFoundError: No module named 'reportlab'
[PYI-33160:ERROR] Failed to execute script 'app2' due to unhandled exception!


At first I got the same error for the flask module and I solved it with the following lines at the beginning of my script:

import os
os.system('pip install flask')


But I am afraid installing each module each time the programm starts would make it unnecessarily slow. Is there another solution than another a 'pip install reportlab' statement?

I am using python version 3.11.9

Continue reading...