Getting Error ImportError: No module named flask

[Abhijeet241093]

Traceback (most recent call last):
File "run.py", line 12, in
from annotation_tools.annotation_tools import app
File "/media/phuongnd/SSD_DATA/annotation_tools/annotation_tools/annotation_tools.py", line 13, in
from flask import Flask, render_template, jsonify, request
ImportError: No module named flask