new_contents: #-*- coding=utf-8 -*-
  
  import os
  from flask import Flask, request, redirect, url_for
  from werkzeug import secure_filename
  
  UPLOAD_FOLDER = '/tmp/file'
  ALLOWED_EXTENSIONS = {'txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif'}
  app = Flask(__name__)
  app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
  
  #@app.route('/')
  #def hello_world():
  #    return 'Hello world'
  
  def allowed_file(filename):
      return '.' in filename and \
              filename.rsplit('.', 1)[1] in ALLOWED_EXTENSIONS
              
  @app.route('/', methods=['GET', 'POST'])
  def upload_file():
      if request.method == 'POST':
          file = request.files['file']
          if file and allowed_file(file.filename):
              filename = secure_filename(file.filename)
              file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
              return redirect(url_for('upload_file', filename=filename))
      return '''
      <!doctype html>
      <title>Upload new File</title>
      <h1>Upload new File</h1>
      <form action="" method=post enctype=multipart/form-data>
      <p><input type=file name=file>
          <input type=submit value=Upload>
      </form>
      '''
  
          
  if __name__ == "__main__":
      app.run('0.0.0.0')
  
subject: add hello.py