我正在尝试找出为什么会看到错误
模块未找到错误：没有名为“urlparse”的模块
但我从来不在代码中调用urlparse。
当我尝试用pip安装urlparse时，我看到这个模块不存在。当我尝试用pip安装urllib.parse时，我看到同样的消息：
找不到urllib.parse的匹配分发
我错过了什么？

from flask import Flask, request, redirect, url_for, session, g, flash, \
render_template
from flask_oauth import OAuth

from sqlalchemy import create_engine, Column, Integer, String
from sqlalchemy.orm import scoped_session, sessionmaker
from sqlalchemy.ext.declarative import declarative_base

# configuration
SECRET_KEY = 'development key'
DEBUG = True

# setup flask
app = Flask(__name__)
app.debug = DEBUG
app.secret_key = SECRET_KEY
oauth = OAuth()

# Use Twitter as example remote app
twitter = oauth.remote_app('twitter',
   base_url='https://api.twitter.com/1/',
   request_token_url='https://api.twitter.com/oauth/request_token',
   access_token_url='https://api.twitter.com/oauth/access_token',
   authorize_url='https://api.twitter.com/oauth/authenticate',
   consumer_key='',
   consumer_secret=''
)

@twitter.tokengetter
def get_twitter_token(token=None):
    return session.get('twitter_token')

@app.route('/')
def index():
    access_token = session.get('access_token')
    if access_token is None:
        return redirect(url_for('login'))
    access_token = access_token[0]
    return render_template('templates/index.html')

if __name__ == '__main__':
    app.run()