from flask import Flask, render_template, request, jsonify
app = Flask(__name__)

from pymongo import MongoClient
import certifi

ca = certifi.where()
client = MongoClient('mongodb+srv://test:sparta@cluster0.gsi1wh0.mongodb.net/Cluster0?retryWrites=true&w=majority',tlsCAFile = ca)
db = client.dbsparta

@app.route('/')
def home():
 return render_template('index.html')

@app.route("/mars", methods=["POST"])
def web_mars_post():
   name_receive = request.form['name_give']
   address_receive = request.form['address_give']
   size_receive = request.form['size_give']

   doc = {
       'name':name_receive,
       'address':address_receive,
       'size':size_receive
   }
   db.mars.insert_one(doc)

   return jsonify({'msg': '주문 완료'})

@app.route("/mars", methods=["GET"])
def web_mars_get():
  return jsonify({'msg': 'GET 연결 완료!'})

if __name__ == '__main__':
 app.run('0.0.0.0', port=5000, debug=True)

"C:\Users\user\OneDrive\바탕 화면\sparta\projects\mars\venv\Scripts\python.exe" "C:/Users/user/OneDrive/바탕 화면/sparta/projects/mars/app.py"

Traceback (most recent call last):

 File "C:/Users/user/OneDrive/바탕 화면/sparta/projects/mars/app.py", line 5, in <module>

  import certifi

ModuleNotFoundError: No module named 'certifi'

종료 코드 1(으)로 완료된 프로세스

이렇게 에러표시가 나타나는데 무엇이 문제입니까...