Python CGI Runtime Error

Traceback (most recent call last):
  File "index.cgi", line 16, in 
    from app import app
  File "/home/netten07/netten-cloud.net/public_html/app.netten-cloud.net/app.py", line 8, in 
    from flask import Flask, render_template, request, jsonify
ModuleNotFoundError: No module named 'flask'