我有一个简单的python文件，尝试将其设置为使用会话，当我运行该文件时，出现以下错误：
ModuleNotFoundError：没有名为“ flask_session”的模块
我相信我已正确导入了模块，是否还有其他可以检查以正确设置的模块？
from flask import Flask, render_template, request, session
from flask_session import Session
app = Flask(__name__)
app.config["SESSION_PERMANENT"] = False
app.config["SESSION_TYPE"] = "filesystem"
Session(app)
@app.route("/", methods=["GET", "POST"])
def index():
if session.get("notes") is None:
session["notes"] = []
if request.method == "POST":
note = request.form.get("note")
session["notes"].append(note)
return render_template("index.html", notes=notes)
这是回溯（最近一次拨打电话）
File "c:\python37\lib\site-packages\flask\cli.py", line 325, in __call__
Open an interactive python shell in this frameself._flush_bg_loading_exception()
File "c:\python37\lib\site-packages\flask\cli.py", line 313, in _flush_bg_loading_exception
reraise(*exc_info)
File "c:\python37\lib\site-packages\flask\_compat.py", line 35, in reraise
raise value
File "c:\python37\lib\site-packages\flask\cli.py", …