title: flask_uploads: ImportError: cannot import name 'secure_filename'
body: <p>I want to create a form that allows to send a picture with a description using flask forms.
  I tried to use this video: <a href="https://www.youtube.com/watch?v=Exf8RbgKmhM" rel="noreferrer">https://www.youtube.com/watch?v=Exf8RbgKmhM</a></p>
  
  <p>but I had troubles when launching app.py:</p>
  
  <pre><code>➜  website git:(master) ✗ python3.6 app.py
  Traceback (most recent call last):
    File "app.py", line 10, in &lt;module&gt;
      from flask.ext.uploads import UploadSet, configure_uploads, IMAGES
  ModuleNotFoundError: No module named 'flask.ext'
  </code></pre>
  
  <p>I had to replace
  <code>flask.ext.uploads</code> by <code>flask_uploads</code>
  but now I get:</p>
  
  <pre><code>Traceback (most recent call last):
    File "app.py", line 10, in &lt;module&gt;
      from flask_uploads import UploadSet, configure_uploads, IMAGES
    File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/flask_uploads.py", line 26, in &lt;module&gt;
      from werkzeug import secure_filename, FileStorage
  ImportError: cannot import name 'secure_filename'
  </code></pre>
  
  <p>My imports and config looks like this:</p>
  
  <pre><code>from datetime import datetime
  from flask_sqlalchemy import SQLAlchemy
  from flask import Flask, session, render_template, url_for, redirect, flash, request
  from wtforms import Form, fields,TextField, StringField, PasswordField, BooleanField,validators
  from wtforms.validators import InputRequired, Email, Length, DataRequired
  from flask_wtf import FlaskForm
  from flask_uploads import UploadSet, configure_uploads, IMAGES
  from flask_login import LoginManager, UserMixin, login_user, login_required, logout_user, current_user
  </code></pre>
  
  <p>I couldn't solve this issue, do you have any idea of what can I do ?</p>