input: Write a function to create a Flask web application that takes user input through a form and generates an HTML page displaying the input. Return the Flask app object.
  assert web_app().route('/', methods=['GET'])()=="""
  <html>
   <body>
    <h1>Your Input: </h1>
    <p>{{input_text}}</p>
   </body>
  </html>
  """
  assert web_app().route('/', methods=['POST'])()=="""
  <html>
   <body>
    <h1>Your Input: </h1>
    <p>{{input_text}}</p>
   </body>
  </html>
  """
  assert web_app().run.__name__ == "run"
output: from flask import Flask, request, render_template_string
  
  def web_app():
      app = Flask(__name__)
  
      @app.route('/', methods=['GET'])
      def index_get():
          return render_template_string("""
  <html>
   <body>
    <h1>Your Input: </h1>
    <p>{{input_text}}</p>
   </body>
  </html>
  """, input_text="")
  
      @app.route('/', methods=['POST'])
      def index_post():
          input_text = request.form.get('input_text', '')
          return render_template_string("""
  <html>
   <body>
    <h1>Your Input: </h1>
    <p>{{input_text}}</p>
   </body>
  </html>
  """, input_text=input_text)
  
      return app